<?xml version="1.0" encoding="UTF-8"?>

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2026 Workiva-->
<!--r:019e6fc4-59f0-7aa8-937a-5de69b01093c,g:eb64c34f-dcdc-4f2d-ad8c-8466ea082266-->
<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/all" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#hypercube-dimension"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-default"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-domain"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member"/>
  <link:roleRef roleURI="http://www.scotts.com/role/SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIESAdditionalInformationDetails" xlink:type="simple" xlink:href="smg-20260627.xsd#SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIESAdditionalInformationDetails"/>
  <link:definitionLink xlink:role="http://www.scotts.com/role/SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIESAdditionalInformationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_smg_SignificantAccountingPoliciesLineItems_019e6fc4-5d02-7f5c-8447-9ce6fb7414dc" xlink:href="smg-20260627.xsd#smg_SignificantAccountingPoliciesLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_SignificantAccountingPoliciesTable_019e6fc4-5d02-7665-914f-3c190cad41de" xlink:href="smg-20260627.xsd#smg_SignificantAccountingPoliciesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_smg_SignificantAccountingPoliciesLineItems_019e6fc4-5d02-7f5c-8447-9ce6fb7414dc" xlink:to="loc_smg_SignificantAccountingPoliciesTable_019e6fc4-5d02-7665-914f-3c190cad41de" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesAxis_019e6fc4-5d02-7485-9763-6855ac3b1e6b" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_smg_SignificantAccountingPoliciesTable_019e6fc4-5d02-7665-914f-3c190cad41de" xlink:to="loc_srt_ConsolidatedEntitiesAxis_019e6fc4-5d02-7485-9763-6855ac3b1e6b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_019e6fc4-5d02-7485-9763-6855ac3b1e6b_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidatedEntitiesAxis_019e6fc4-5d02-7485-9763-6855ac3b1e6b" xlink:to="loc_srt_ConsolidatedEntitiesDomain_019e6fc4-5d02-7485-9763-6855ac3b1e6b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidatedEntitiesDomain_019e6fc4-5d02-7f08-b57d-d9fcbf3a2acc" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidatedEntitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidatedEntitiesAxis_019e6fc4-5d02-7485-9763-6855ac3b1e6b" xlink:to="loc_srt_ConsolidatedEntitiesDomain_019e6fc4-5d02-7f08-b57d-d9fcbf3a2acc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableInterestEntityPrimaryBeneficiaryMember_019e6fc4-5d02-7eb8-a7f0-ace4e953f178" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VariableInterestEntityPrimaryBeneficiaryMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidatedEntitiesDomain_019e6fc4-5d02-7f08-b57d-d9fcbf3a2acc" xlink:to="loc_us-gaap_VariableInterestEntityPrimaryBeneficiaryMember_019e6fc4-5d02-7eb8-a7f0-ace4e953f178" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityAxis_019e6fc4-5d02-792c-b0fa-2b6e2c1c0e5f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_smg_SignificantAccountingPoliciesTable_019e6fc4-5d02-7665-914f-3c190cad41de" xlink:to="loc_us-gaap_CreditFacilityAxis_019e6fc4-5d02-792c-b0fa-2b6e2c1c0e5f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_019e6fc4-5d02-792c-b0fa-2b6e2c1c0e5f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditFacilityAxis_019e6fc4-5d02-792c-b0fa-2b6e2c1c0e5f" xlink:to="loc_us-gaap_CreditFacilityDomain_019e6fc4-5d02-792c-b0fa-2b6e2c1c0e5f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_019e6fc4-5d02-77c0-a899-f34a62c03ed9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditFacilityAxis_019e6fc4-5d02-792c-b0fa-2b6e2c1c0e5f" xlink:to="loc_us-gaap_CreditFacilityDomain_019e6fc4-5d02-77c0-a899-f34a62c03ed9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StandbyLettersOfCreditMember_019e6fc4-5d02-7441-885c-b714f92f6fe5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StandbyLettersOfCreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_019e6fc4-5d02-77c0-a899-f34a62c03ed9" xlink:to="loc_us-gaap_StandbyLettersOfCreditMember_019e6fc4-5d02-7441-885c-b714f92f6fe5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_019e6fc4-5d02-7eaf-8be5-8812d5245052" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_smg_SignificantAccountingPoliciesTable_019e6fc4-5d02-7665-914f-3c190cad41de" xlink:to="loc_srt_RangeAxis_019e6fc4-5d02-7eaf-8be5-8812d5245052" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019e6fc4-5d02-7eaf-8be5-8812d5245052_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_019e6fc4-5d02-7eaf-8be5-8812d5245052" xlink:to="loc_srt_RangeMember_019e6fc4-5d02-7eaf-8be5-8812d5245052_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019e6fc4-5d02-72b2-ae5e-c1fb85f2028a" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_019e6fc4-5d02-7eaf-8be5-8812d5245052" xlink:to="loc_srt_RangeMember_019e6fc4-5d02-72b2-ae5e-c1fb85f2028a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_019e6fc4-5d02-7352-b25c-f849140f901e" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019e6fc4-5d02-72b2-ae5e-c1fb85f2028a" xlink:to="loc_srt_MaximumMember_019e6fc4-5d02-7352-b25c-f849140f901e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_019e6fc4-5d02-7f86-a311-fd3d181abb18" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019e6fc4-5d02-72b2-ae5e-c1fb85f2028a" xlink:to="loc_srt_MinimumMember_019e6fc4-5d02-7f86-a311-fd3d181abb18" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationAxis_019fabc3-f20b-76bf-8c62-e934360ba141" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupClassificationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_smg_SignificantAccountingPoliciesTable_019e6fc4-5d02-7665-914f-3c190cad41de" xlink:to="loc_us-gaap_DisposalGroupClassificationAxis_019fabc3-f20b-76bf-8c62-e934360ba141" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationDomain_019fabc3-f20b-76bf-8c62-e934360ba141_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DisposalGroupClassificationAxis_019fabc3-f20b-76bf-8c62-e934360ba141" xlink:to="loc_us-gaap_DisposalGroupClassificationDomain_019fabc3-f20b-76bf-8c62-e934360ba141_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationDomain_019fabc3-f20b-71bb-bb82-b31adc1aec27" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DisposalGroupClassificationAxis_019fabc3-f20b-76bf-8c62-e934360ba141" xlink:to="loc_us-gaap_DisposalGroupClassificationDomain_019fabc3-f20b-71bb-bb82-b31adc1aec27" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DiscontinuedOperationsHeldforsaleMember_019fabc3-f20b-705f-8636-8449906e542e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DiscontinuedOperationsHeldforsaleMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupClassificationDomain_019fabc3-f20b-71bb-bb82-b31adc1aec27" xlink:to="loc_us-gaap_DiscontinuedOperationsHeldforsaleMember_019fabc3-f20b-705f-8636-8449906e542e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_PercentageOfAnnualNetSales_019e6fc4-5d02-74ba-88f1-5f8d0c896704" xlink:href="smg-20260627.xsd#smg_PercentageOfAnnualNetSales"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_SignificantAccountingPoliciesLineItems_019e6fc4-5d02-7f5c-8447-9ce6fb7414dc" xlink:to="loc_smg_PercentageOfAnnualNetSales_019e6fc4-5d02-74ba-88f1-5f8d0c896704" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Liabilities_019e6fc4-5d02-721e-b75e-3059d19c3aaf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Liabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_SignificantAccountingPoliciesLineItems_019e6fc4-5d02-7f5c-8447-9ce6fb7414dc" xlink:to="loc_us-gaap_Liabilities_019e6fc4-5d02-721e-b75e-3059d19c3aaf" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_InvestmentsSoldBookValue_019e6fc4-5d02-7987-8b5f-8cfe7b9bfb63" xlink:href="smg-20260627.xsd#smg_InvestmentsSoldBookValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_SignificantAccountingPoliciesLineItems_019e6fc4-5d02-7f5c-8447-9ce6fb7414dc" xlink:to="loc_smg_InvestmentsSoldBookValue_019e6fc4-5d02-7987-8b5f-8cfe7b9bfb63" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_019e6fc4-5d02-7aad-bb04-c394d16eeaf0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Assets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_SignificantAccountingPoliciesLineItems_019e6fc4-5d02-7f5c-8447-9ce6fb7414dc" xlink:to="loc_us-gaap_Assets_019e6fc4-5d02-7aad-bb04-c394d16eeaf0" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_CallOptionPercentageOfAppreciationOfFairValue_019e6fc4-5d02-7414-a521-93447a6e48d0" xlink:href="smg-20260627.xsd#smg_CallOptionPercentageOfAppreciationOfFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_SignificantAccountingPoliciesLineItems_019e6fc4-5d02-7f5c-8447-9ce6fb7414dc" xlink:to="loc_smg_CallOptionPercentageOfAppreciationOfFairValue_019e6fc4-5d02-7414-a521-93447a6e48d0" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestments_019e6fc4-5d02-76ec-94d3-5de93f4cd856" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityMethodInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_SignificantAccountingPoliciesLineItems_019e6fc4-5d02-7f5c-8447-9ce6fb7414dc" xlink:to="loc_us-gaap_EquityMethodInvestments_019e6fc4-5d02-76ec-94d3-5de93f4cd856" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherAssetsNoncurrent_019e6fc4-5d02-7c2e-84ea-39ebc4a65a0b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherAssetsNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_SignificantAccountingPoliciesLineItems_019e6fc4-5d02-7f5c-8447-9ce6fb7414dc" xlink:to="loc_us-gaap_OtherAssetsNoncurrent_019e6fc4-5d02-7c2e-84ea-39ebc4a65a0b" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TradeReceivablesHeldForSaleAmount_019e6fc4-5d02-78c8-9460-0c4e644f4f62" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TradeReceivablesHeldForSaleAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_SignificantAccountingPoliciesLineItems_019e6fc4-5d02-7f5c-8447-9ce6fb7414dc" xlink:to="loc_us-gaap_TradeReceivablesHeldForSaleAmount_019e6fc4-5d02-78c8-9460-0c4e644f4f62" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_019e6fc4-5d02-74b0-9cfa-850349542298" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_SignificantAccountingPoliciesLineItems_019e6fc4-5d02-7f5c-8447-9ce6fb7414dc" xlink:to="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_019e6fc4-5d02-74b0-9cfa-850349542298" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInReceivables_019e6fc4-5d02-7f96-989b-190a16a9fe45" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInReceivables"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_SignificantAccountingPoliciesLineItems_019e6fc4-5d02-7f5c-8447-9ce6fb7414dc" xlink:to="loc_us-gaap_IncreaseDecreaseInReceivables_019e6fc4-5d02-7f96-989b-190a16a9fe45" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_DiscountOnSaleOfOtherReceivables_019e6fc4-5d02-749c-9883-44e461a400f2" xlink:href="smg-20260627.xsd#smg_DiscountOnSaleOfOtherReceivables"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_SignificantAccountingPoliciesLineItems_019e6fc4-5d02-7f5c-8447-9ce6fb7414dc" xlink:to="loc_smg_DiscountOnSaleOfOtherReceivables_019e6fc4-5d02-749c-9883-44e461a400f2" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromSaleOfOtherReceivables_019e6fc4-5d02-7468-a209-05a74a0d207e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromSaleOfOtherReceivables"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_SignificantAccountingPoliciesLineItems_019e6fc4-5d02-7f5c-8447-9ce6fb7414dc" xlink:to="loc_us-gaap_ProceedsFromSaleOfOtherReceivables_019e6fc4-5d02-7468-a209-05a74a0d207e" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SupplierFinanceProgramPaymentTimingPeriod_019e6fc4-5d02-73c6-a5f5-19bfb4a9cda5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SupplierFinanceProgramPaymentTimingPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_SignificantAccountingPoliciesLineItems_019e6fc4-5d02-7f5c-8447-9ce6fb7414dc" xlink:to="loc_us-gaap_SupplierFinanceProgramPaymentTimingPeriod_019e6fc4-5d02-73c6-a5f5-19bfb4a9cda5" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SupplierFinanceProgramObligation_019e6fc4-5d02-72ad-bb71-cd2ef86b8b11" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SupplierFinanceProgramObligation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_SignificantAccountingPoliciesLineItems_019e6fc4-5d02-7f5c-8447-9ce6fb7414dc" xlink:to="loc_us-gaap_SupplierFinanceProgramObligation_019e6fc4-5d02-72ad-bb71-cd2ef86b8b11" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SupplierFinanceProgramObligationDecreaseSettlement_019e6fc4-5d02-74df-b6a4-909a095f724d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SupplierFinanceProgramObligationDecreaseSettlement"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_SignificantAccountingPoliciesLineItems_019e6fc4-5d02-7f5c-8447-9ce6fb7414dc" xlink:to="loc_us-gaap_SupplierFinanceProgramObligationDecreaseSettlement_019e6fc4-5d02-74df-b6a4-909a095f724d" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CapitalExpendituresIncurredButNotYetPaid_019e6fc4-5d02-7f2c-a241-3465550b52ce" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CapitalExpendituresIncurredButNotYetPaid"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_SignificantAccountingPoliciesLineItems_019e6fc4-5d02-7f5c-8447-9ce6fb7414dc" xlink:to="loc_us-gaap_CapitalExpendituresIncurredButNotYetPaid_019e6fc4-5d02-7f2c-a241-3465550b52ce" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationCashAndCashEquivalents_019e6fc4-5d02-7bc0-b3eb-7c45041718cc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationCashAndCashEquivalents"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_SignificantAccountingPoliciesLineItems_019e6fc4-5d02-7f5c-8447-9ce6fb7414dc" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationCashAndCashEquivalents_019e6fc4-5d02-7bc0-b3eb-7c45041718cc" xlink:type="arc" order="16"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.scotts.com/role/DISCONTINUEDOPERATIONSNarrativeDetails" xlink:type="simple" xlink:href="smg-20260627.xsd#DISCONTINUEDOPERATIONSNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.scotts.com/role/DISCONTINUEDOPERATIONSNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019e6fc4-5d02-7950-b8b4-5b327a9c89af" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_019e6fc4-5d02-78bb-ba59-15fe7ca4b6e6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019e6fc4-5d02-7950-b8b4-5b327a9c89af" xlink:to="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_019e6fc4-5d02-78bb-ba59-15fe7ca4b6e6" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationAxis_019e6fc4-5d02-7c4c-9581-a309662ff22b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupClassificationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_019e6fc4-5d02-78bb-ba59-15fe7ca4b6e6" xlink:to="loc_us-gaap_DisposalGroupClassificationAxis_019e6fc4-5d02-7c4c-9581-a309662ff22b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationDomain_019e6fc4-5d02-7c4c-9581-a309662ff22b_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DisposalGroupClassificationAxis_019e6fc4-5d02-7c4c-9581-a309662ff22b" xlink:to="loc_us-gaap_DisposalGroupClassificationDomain_019e6fc4-5d02-7c4c-9581-a309662ff22b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationDomain_019e6fc4-5d02-7158-b2e6-7f90aae3af45" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DisposalGroupClassificationAxis_019e6fc4-5d02-7c4c-9581-a309662ff22b" xlink:to="loc_us-gaap_DisposalGroupClassificationDomain_019e6fc4-5d02-7158-b2e6-7f90aae3af45" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DiscontinuedOperationsDisposedOfBySaleMember_019e6fc4-5d02-77a5-bca9-30ab94d19e70" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DiscontinuedOperationsDisposedOfBySaleMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupClassificationDomain_019e6fc4-5d02-7158-b2e6-7f90aae3af45" xlink:to="loc_us-gaap_DiscontinuedOperationsDisposedOfBySaleMember_019e6fc4-5d02-77a5-bca9-30ab94d19e70" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DiscontinuedOperationsHeldforsaleMember_019e6fc4-5d02-77e5-abc7-162faab92ba3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DiscontinuedOperationsHeldforsaleMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupClassificationDomain_019e6fc4-5d02-7158-b2e6-7f90aae3af45" xlink:to="loc_us-gaap_DiscontinuedOperationsHeldforsaleMember_019e6fc4-5d02-77e5-abc7-162faab92ba3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_OwnershipAxis_019e6fc4-5d02-77f9-ab28-3c05a4096c3a" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_OwnershipAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_019e6fc4-5d02-78bb-ba59-15fe7ca4b6e6" xlink:to="loc_srt_OwnershipAxis_019e6fc4-5d02-77f9-ab28-3c05a4096c3a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_OwnershipDomain_019e6fc4-5d02-77f9-ab28-3c05a4096c3a_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_OwnershipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_OwnershipAxis_019e6fc4-5d02-77f9-ab28-3c05a4096c3a" xlink:to="loc_srt_OwnershipDomain_019e6fc4-5d02-77f9-ab28-3c05a4096c3a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_OwnershipDomain_019e6fc4-5d02-7166-810d-7cd0680d3d81" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_OwnershipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_OwnershipAxis_019e6fc4-5d02-77f9-ab28-3c05a4096c3a" xlink:to="loc_srt_OwnershipDomain_019e6fc4-5d02-7166-810d-7cd0680d3d81" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_VireoGrowthInc.Member_019e6fc4-5d02-74f8-aeb3-7b71c6d96e13" xlink:href="smg-20260627.xsd#smg_VireoGrowthInc.Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_OwnershipDomain_019e6fc4-5d02-7166-810d-7cd0680d3d81" xlink:to="loc_smg_VireoGrowthInc.Member_019e6fc4-5d02-74f8-aeb3-7b71c6d96e13" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_019e6fc4-5d02-7225-836c-f5779641a1e2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_019e6fc4-5d02-78bb-ba59-15fe7ca4b6e6" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_019e6fc4-5d02-7225-836c-f5779641a1e2" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_019e6fc4-5d02-7225-836c-f5779641a1e2_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_019e6fc4-5d02-7225-836c-f5779641a1e2" xlink:to="loc_us-gaap_SegmentDomain_019e6fc4-5d02-7225-836c-f5779641a1e2_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_019e6fc4-5d02-7893-acf7-371991f35c1f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_019e6fc4-5d02-7225-836c-f5779641a1e2" xlink:to="loc_us-gaap_SegmentDomain_019e6fc4-5d02-7893-acf7-371991f35c1f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_HawthorneMember_019e6fc4-5d02-7af1-99d5-6a4100a9b277" xlink:href="smg-20260627.xsd#smg_HawthorneMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_019e6fc4-5d02-7893-acf7-371991f35c1f" xlink:to="loc_smg_HawthorneMember_019e6fc4-5d02-7af1-99d5-6a4100a9b277" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_DisposalGroupIncludingDiscontinuedOperationConsiderationShares_019e6fc4-5d02-7e57-ada6-a1cd97baa224" xlink:href="smg-20260627.xsd#smg_DisposalGroupIncludingDiscontinuedOperationConsiderationShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019e6fc4-5d02-7950-b8b4-5b327a9c89af" xlink:to="loc_smg_DisposalGroupIncludingDiscontinuedOperationConsiderationShares_019e6fc4-5d02-7e57-ada6-a1cd97baa224" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedPercentOfNetAssets_019e6fc4-5d02-72ae-ae8e-a87fb3637a05" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedPercentOfNetAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019e6fc4-5d02-7950-b8b4-5b327a9c89af" xlink:to="loc_us-gaap_InvestmentOwnedPercentOfNetAssets_019e6fc4-5d02-72ae-ae8e-a87fb3637a05" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WarrantsAndRightsOutstandingTerm_019e6fc4-5d02-7c61-a6d7-9aec138b3835" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_WarrantsAndRightsOutstandingTerm"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019e6fc4-5d02-7950-b8b4-5b327a9c89af" xlink:to="loc_us-gaap_WarrantsAndRightsOutstandingTerm_019e6fc4-5d02-7c61-a6d7-9aec138b3835" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights_019e6fc4-5d02-7623-a1e9-b0696b3ff0dc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019e6fc4-5d02-7950-b8b4-5b327a9c89af" xlink:to="loc_us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights_019e6fc4-5d02-7623-a1e9-b0696b3ff0dc" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_019e6fc4-5d02-752d-94ca-69e1df4d6426" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019e6fc4-5d02-7950-b8b4-5b327a9c89af" xlink:to="loc_us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_019e6fc4-5d02-752d-94ca-69e1df4d6426" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_019e6fc4-5d02-7b7d-9cb8-e7bac6ab45ab" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019e6fc4-5d02-7950-b8b4-5b327a9c89af" xlink:to="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_019e6fc4-5d02-7b7d-9cb8-e7bac6ab45ab" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherCommitment_019e6fc4-5d02-73cc-b4c5-57ce158f1e54" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherCommitment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019e6fc4-5d02-7950-b8b4-5b327a9c89af" xlink:to="loc_us-gaap_OtherCommitment_019e6fc4-5d02-73cc-b4c5-57ce158f1e54" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DiscontinuedOperationPeriodOfContinuingInvolvementAfterDisposal_019e6fc4-5d02-76fa-9583-d39c6b76d388" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DiscontinuedOperationPeriodOfContinuingInvolvementAfterDisposal"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019e6fc4-5d02-7950-b8b4-5b327a9c89af" xlink:to="loc_us-gaap_DiscontinuedOperationPeriodOfContinuingInvolvementAfterDisposal_019e6fc4-5d02-76fa-9583-d39c6b76d388" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_NumberOfVariableInterestEntityBoardMembers_019e6fc4-5d02-7dbf-9220-d5447eb679f5" xlink:href="smg-20260627.xsd#smg_NumberOfVariableInterestEntityBoardMembers"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019e6fc4-5d02-7950-b8b4-5b327a9c89af" xlink:to="loc_smg_NumberOfVariableInterestEntityBoardMembers_019e6fc4-5d02-7dbf-9220-d5447eb679f5" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DiscontinuedOperationAmountOfAdjustmentToPriorPeriodGainLossOnDisposalNetOfTax_019e6fc4-5d02-7ea4-bc08-e5b7fbd16f79" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DiscontinuedOperationAmountOfAdjustmentToPriorPeriodGainLossOnDisposalNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019e6fc4-5d02-7950-b8b4-5b327a9c89af" xlink:to="loc_us-gaap_DiscontinuedOperationAmountOfAdjustmentToPriorPeriodGainLossOnDisposalNetOfTax_019e6fc4-5d02-7ea4-bc08-e5b7fbd16f79" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations_019fc98b-c11f-72fe-abd8-b6145580a9f0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019e6fc4-5d02-7950-b8b4-5b327a9c89af" xlink:to="loc_us-gaap_CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations_019fc98b-c11f-72fe-abd8-b6145580a9f0" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtFairValue_019fcdbf-5ddc-71c3-aac3-110b2d5319ce" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019e6fc4-5d02-7950-b8b4-5b327a9c89af" xlink:to="loc_us-gaap_InvestmentOwnedAtFairValue_019fcdbf-5ddc-71c3-aac3-110b2d5319ce" xlink:type="arc" order="11"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.scotts.com/role/DISCONTINUEDOPERATIONSSummaryofFinancialResultsDetails" xlink:type="simple" xlink:href="smg-20260627.xsd#DISCONTINUEDOPERATIONSSummaryofFinancialResultsDetails"/>
  <link:definitionLink xlink:role="http://www.scotts.com/role/DISCONTINUEDOPERATIONSSummaryofFinancialResultsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019e6fc4-5d02-73aa-a81d-20b2e614c9b0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_019e6fc4-5d02-79c3-b91f-2e7536c8690e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019e6fc4-5d02-73aa-a81d-20b2e614c9b0" xlink:to="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_019e6fc4-5d02-79c3-b91f-2e7536c8690e" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationAxis_019e6fc4-5d02-7a70-8831-afca6cd7a7c0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupClassificationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_019e6fc4-5d02-79c3-b91f-2e7536c8690e" xlink:to="loc_us-gaap_DisposalGroupClassificationAxis_019e6fc4-5d02-7a70-8831-afca6cd7a7c0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationDomain_019e6fc4-5d02-7a70-8831-afca6cd7a7c0_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DisposalGroupClassificationAxis_019e6fc4-5d02-7a70-8831-afca6cd7a7c0" xlink:to="loc_us-gaap_DisposalGroupClassificationDomain_019e6fc4-5d02-7a70-8831-afca6cd7a7c0_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationDomain_019e6fc4-5d02-7b27-9697-7fbe723f5bd4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DisposalGroupClassificationAxis_019e6fc4-5d02-7a70-8831-afca6cd7a7c0" xlink:to="loc_us-gaap_DisposalGroupClassificationDomain_019e6fc4-5d02-7b27-9697-7fbe723f5bd4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DiscontinuedOperationsHeldforsaleMember_019e6fc4-5d02-73b5-99fd-9060e5281ed9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DiscontinuedOperationsHeldforsaleMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupClassificationDomain_019e6fc4-5d02-7b27-9697-7fbe723f5bd4" xlink:to="loc_us-gaap_DiscontinuedOperationsHeldforsaleMember_019e6fc4-5d02-73b5-99fd-9060e5281ed9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationRevenue_019e6fc4-5d02-7409-9b2e-9da8ed75e21c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationRevenue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019e6fc4-5d02-73aa-a81d-20b2e614c9b0" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationRevenue_019e6fc4-5d02-7409-9b2e-9da8ed75e21c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_DisposalGroupIncludingDiscontinuedOperationCostsOfGoodsSoldNetOfRefund_019fce94-02c0-7ca3-be6e-5a2de6b0ebdc" xlink:href="smg-20260627.xsd#smg_DisposalGroupIncludingDiscontinuedOperationCostsOfGoodsSoldNetOfRefund"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019e6fc4-5d02-73aa-a81d-20b2e614c9b0" xlink:to="loc_smg_DisposalGroupIncludingDiscontinuedOperationCostsOfGoodsSoldNetOfRefund_019fce94-02c0-7ca3-be6e-5a2de6b0ebdc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationCostsOfGoodsSold_019e6fc4-5d02-7196-b5c4-64e27982822f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationCostsOfGoodsSold"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019e6fc4-5d02-73aa-a81d-20b2e614c9b0" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationCostsOfGoodsSold_019e6fc4-5d02-7196-b5c4-64e27982822f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_DisposalGroupIncludingDiscontinuedOperationCostOfSalesImpairmentRestructuringAndOtherCharges_019e6fc4-5d02-7f4f-aafc-0282c0223f6f" xlink:href="smg-20260627.xsd#smg_DisposalGroupIncludingDiscontinuedOperationCostOfSalesImpairmentRestructuringAndOtherCharges"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019e6fc4-5d02-73aa-a81d-20b2e614c9b0" xlink:to="loc_smg_DisposalGroupIncludingDiscontinuedOperationCostOfSalesImpairmentRestructuringAndOtherCharges_019e6fc4-5d02-7f4f-aafc-0282c0223f6f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationGeneralAndAdministrativeExpense_019e6fc4-5d02-7c45-a411-b4853b3d53a5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationGeneralAndAdministrativeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019e6fc4-5d02-73aa-a81d-20b2e614c9b0" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationGeneralAndAdministrativeExpense_019e6fc4-5d02-7c45-a411-b4853b3d53a5" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_DisposalGroupIncludingDiscontinuedOperationRestructuringSettlementAndImpairmentProvisions_019e6fc4-5d02-72f3-ad44-b23220b62b89" xlink:href="smg-20260627.xsd#smg_DisposalGroupIncludingDiscontinuedOperationRestructuringSettlementAndImpairmentProvisions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019e6fc4-5d02-73aa-a81d-20b2e614c9b0" xlink:to="loc_smg_DisposalGroupIncludingDiscontinuedOperationRestructuringSettlementAndImpairmentProvisions_019e6fc4-5d02-72f3-ad44-b23220b62b89" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_DisposalGroupIncludingDiscontinuedOperationOtherOperatingIncomeExpenseNet_019e6fc4-5d02-7f8c-a296-e71b48492202" xlink:href="smg-20260627.xsd#smg_DisposalGroupIncludingDiscontinuedOperationOtherOperatingIncomeExpenseNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019e6fc4-5d02-73aa-a81d-20b2e614c9b0" xlink:to="loc_smg_DisposalGroupIncludingDiscontinuedOperationOtherOperatingIncomeExpenseNet_019e6fc4-5d02-7f8c-a296-e71b48492202" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationBeforeIncomeTax_019e6fc4-5d02-771c-be7a-d079579c1c4a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationBeforeIncomeTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019e6fc4-5d02-73aa-a81d-20b2e614c9b0" xlink:to="loc_us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationBeforeIncomeTax_019e6fc4-5d02-771c-be7a-d079579c1c4a" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DiscontinuedOperationAmountOfAdjustmentToPriorPeriodGainLossOnDisposalNetOfTax_019e6fc4-5d02-7b79-b2be-c3a14d0cbba1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DiscontinuedOperationAmountOfAdjustmentToPriorPeriodGainLossOnDisposalNetOfTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019e6fc4-5d02-73aa-a81d-20b2e614c9b0" xlink:to="loc_us-gaap_DiscontinuedOperationAmountOfAdjustmentToPriorPeriodGainLossOnDisposalNetOfTax_019e6fc4-5d02-7b79-b2be-c3a14d0cbba1" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DiscontinuedOperationTaxEffectOfDiscontinuedOperation_019e6fc4-5d02-7fc5-8014-b5d5869766cc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DiscontinuedOperationTaxEffectOfDiscontinuedOperation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019e6fc4-5d02-73aa-a81d-20b2e614c9b0" xlink:to="loc_us-gaap_DiscontinuedOperationTaxEffectOfDiscontinuedOperation_019e6fc4-5d02-7fc5-8014-b5d5869766cc" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity_019e6fc4-5d02-762c-843a-825b925f84c8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019e6fc4-5d02-73aa-a81d-20b2e614c9b0" xlink:to="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity_019e6fc4-5d02-762c-843a-825b925f84c8" xlink:type="arc" order="10"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.scotts.com/role/DISCONTINUEDOPERATIONSSummaryofMajorAssetsandLiabilitiesDetails" xlink:type="simple" xlink:href="smg-20260627.xsd#DISCONTINUEDOPERATIONSSummaryofMajorAssetsandLiabilitiesDetails"/>
  <link:definitionLink xlink:role="http://www.scotts.com/role/DISCONTINUEDOPERATIONSSummaryofMajorAssetsandLiabilitiesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019e6fc4-5d02-7ffd-a100-2f2a3788cfb5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_019e6fc4-5d02-7575-9290-3d0eba265d57" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019e6fc4-5d02-7ffd-a100-2f2a3788cfb5" xlink:to="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_019e6fc4-5d02-7575-9290-3d0eba265d57" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationAxis_019e6fc4-5d02-7c60-8525-dd9296aa1a82" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupClassificationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsTable_019e6fc4-5d02-7575-9290-3d0eba265d57" xlink:to="loc_us-gaap_DisposalGroupClassificationAxis_019e6fc4-5d02-7c60-8525-dd9296aa1a82" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationDomain_019e6fc4-5d02-7c60-8525-dd9296aa1a82_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DisposalGroupClassificationAxis_019e6fc4-5d02-7c60-8525-dd9296aa1a82" xlink:to="loc_us-gaap_DisposalGroupClassificationDomain_019e6fc4-5d02-7c60-8525-dd9296aa1a82_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupClassificationDomain_019e6fc4-5d02-7d58-91d5-ef2231585f2b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupClassificationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DisposalGroupClassificationAxis_019e6fc4-5d02-7c60-8525-dd9296aa1a82" xlink:to="loc_us-gaap_DisposalGroupClassificationDomain_019e6fc4-5d02-7d58-91d5-ef2231585f2b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DiscontinuedOperationsHeldforsaleMember_019e6fc4-5d02-71c0-9e8c-f3fd1f5d42e0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DiscontinuedOperationsHeldforsaleMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisposalGroupClassificationDomain_019e6fc4-5d02-7d58-91d5-ef2231585f2b" xlink:to="loc_us-gaap_DiscontinuedOperationsHeldforsaleMember_019e6fc4-5d02-71c0-9e8c-f3fd1f5d42e0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationCashAndCashEquivalents_019e6fc4-5d02-79e6-bd71-c5b22aafc736" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationCashAndCashEquivalents"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019e6fc4-5d02-7ffd-a100-2f2a3788cfb5" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationCashAndCashEquivalents_019e6fc4-5d02-79e6-bd71-c5b22aafc736" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationAccountsNotesAndLoansReceivableNet_019e6fc4-5d02-7bf4-afeb-b6d96d16d7c5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationAccountsNotesAndLoansReceivableNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019e6fc4-5d02-7ffd-a100-2f2a3788cfb5" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationAccountsNotesAndLoansReceivableNet_019e6fc4-5d02-7bf4-afeb-b6d96d16d7c5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationInventoryCurrent_019e6fc4-5d02-705c-a439-73b924d611bf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationInventoryCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019e6fc4-5d02-7ffd-a100-2f2a3788cfb5" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationInventoryCurrent_019e6fc4-5d02-705c-a439-73b924d611bf" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationPrepaidAndOtherAssetsCurrent_019e6fc4-5d02-7fcf-b260-a1fdbfa30962" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationPrepaidAndOtherAssetsCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019e6fc4-5d02-7ffd-a100-2f2a3788cfb5" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationPrepaidAndOtherAssetsCurrent_019e6fc4-5d02-7fcf-b260-a1fdbfa30962" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationPropertyPlantAndEquipmentCurrent_019e6fc4-5d02-792f-b431-0c4ab5cc5695" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationPropertyPlantAndEquipmentCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019e6fc4-5d02-7ffd-a100-2f2a3788cfb5" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationPropertyPlantAndEquipmentCurrent_019e6fc4-5d02-792f-b431-0c4ab5cc5695" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationIntangibleAssetsCurrent_019e6fc4-5d02-7344-bd2d-ad8d8f0f6041" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationIntangibleAssetsCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019e6fc4-5d02-7ffd-a100-2f2a3788cfb5" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationIntangibleAssetsCurrent_019e6fc4-5d02-7344-bd2d-ad8d8f0f6041" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationOtherCurrentAssets_019e6fc4-5d02-7a60-9f36-4d153f53f9b7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationOtherCurrentAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019e6fc4-5d02-7ffd-a100-2f2a3788cfb5" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationOtherCurrentAssets_019e6fc4-5d02-7a60-9f36-4d153f53f9b7" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperation_019e6fc4-5d02-708c-866b-c23e02771aac" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019e6fc4-5d02-7ffd-a100-2f2a3788cfb5" xlink:to="loc_us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperation_019e6fc4-5d02-708c-866b-c23e02771aac" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationAccountsPayableCurrent_019e6fc4-5d02-7aff-9597-be70fecda073" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationAccountsPayableCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019e6fc4-5d02-7ffd-a100-2f2a3788cfb5" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationAccountsPayableCurrent_019e6fc4-5d02-7aff-9597-be70fecda073" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationOtherCurrentLiabilities_019e6fc4-5d02-7efd-8557-2db54bf5c567" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationOtherCurrentLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019e6fc4-5d02-7ffd-a100-2f2a3788cfb5" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationOtherCurrentLiabilities_019e6fc4-5d02-7efd-8557-2db54bf5c567" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationOtherNoncurrentLiabilities_019e6fc4-5d02-78fe-bb4b-8838cd458c15" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisposalGroupIncludingDiscontinuedOperationOtherNoncurrentLiabilities"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019e6fc4-5d02-7ffd-a100-2f2a3788cfb5" xlink:to="loc_us-gaap_DisposalGroupIncludingDiscontinuedOperationOtherNoncurrentLiabilities_019e6fc4-5d02-78fe-bb4b-8838cd458c15" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperation_019e6fc4-5d02-7558-80bb-534c0b295546" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems_019e6fc4-5d02-7ffd-a100-2f2a3788cfb5" xlink:to="loc_us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperation_019e6fc4-5d02-7558-80bb-534c0b295546" xlink:type="arc" order="11"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.scotts.com/role/INVESTMENTINUNCONSOLIDATEDAFFILIATESDetails" xlink:type="simple" xlink:href="smg-20260627.xsd#INVESTMENTINUNCONSOLIDATEDAFFILIATESDetails"/>
  <link:definitionLink xlink:role="http://www.scotts.com/role/INVESTMENTINUNCONSOLIDATEDAFFILIATESDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentInAffiliateActivityLineItems_019e6fc4-5d02-7909-bb7c-9c933a751708" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentInAffiliateActivityLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentsInAndAdvancesToAffiliatesTable_019e6fc4-5d02-74bf-90bc-951461d6caa5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentsInAndAdvancesToAffiliatesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_InvestmentInAffiliateActivityLineItems_019e6fc4-5d02-7909-bb7c-9c933a751708" xlink:to="loc_us-gaap_InvestmentsInAndAdvancesToAffiliatesTable_019e6fc4-5d02-74bf-90bc-951461d6caa5" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019e6fc4-5d02-7b78-b997-1c6d672e677f" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_InvestmentsInAndAdvancesToAffiliatesTable_019e6fc4-5d02-74bf-90bc-951461d6caa5" xlink:to="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019e6fc4-5d02-7b78-b997-1c6d672e677f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_019e6fc4-5d02-7b78-b997-1c6d672e677f_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019e6fc4-5d02-7b78-b997-1c6d672e677f" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_019e6fc4-5d02-7b78-b997-1c6d672e677f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_EquityMethodInvesteeNameDomain_019e6fc4-5d02-76b5-b4d0-6b37c247e5fb" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_EquityMethodInvesteeNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis_019e6fc4-5d02-7b78-b997-1c6d672e677f" xlink:to="loc_srt_EquityMethodInvesteeNameDomain_019e6fc4-5d02-76b5-b4d0-6b37c247e5fb" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_BonniePlantsLLCMember_019e6fc4-5d02-7fa3-bda6-e989edcdf916" xlink:href="smg-20260627.xsd#smg_BonniePlantsLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_019e6fc4-5d02-76b5-b4d0-6b37c247e5fb" xlink:to="loc_smg_BonniePlantsLLCMember_019e6fc4-5d02-7fa3-bda6-e989edcdf916" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_FluentMember_019e6fc4-5d02-739e-8827-3ac7e4f75eb2" xlink:href="smg-20260627.xsd#smg_FluentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_EquityMethodInvesteeNameDomain_019e6fc4-5d02-76b5-b4d0-6b37c247e5fb" xlink:to="loc_smg_FluentMember_019e6fc4-5d02-739e-8827-3ac7e4f75eb2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestmentOwnershipPercentage_019e6fc4-5d03-73a4-86c2-bf7996d0d258" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityMethodInvestmentOwnershipPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentInAffiliateActivityLineItems_019e6fc4-5d02-7909-bb7c-9c933a751708" xlink:to="loc_us-gaap_EquityMethodInvestmentOwnershipPercentage_019e6fc4-5d03-73a4-86c2-bf7996d0d258" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromEquityMethodInvestments_019e6fc4-5d03-73ed-a125-6e0b0964f4ab" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromEquityMethodInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentInAffiliateActivityLineItems_019e6fc4-5d02-7909-bb7c-9c933a751708" xlink:to="loc_us-gaap_IncomeLossFromEquityMethodInvestments_019e6fc4-5d03-73ed-a125-6e0b0964f4ab" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_CommonSharesAcquired_019e6fc4-5d03-75bb-b8d2-03cb81566259" xlink:href="smg-20260627.xsd#smg_CommonSharesAcquired"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentInAffiliateActivityLineItems_019e6fc4-5d02-7909-bb7c-9c933a751708" xlink:to="loc_smg_CommonSharesAcquired_019e6fc4-5d03-75bb-b8d2-03cb81566259" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_ExchangeableSharesConversionRatio_019e6fc4-5d03-755b-a9eb-33b00108029b" xlink:href="smg-20260627.xsd#smg_ExchangeableSharesConversionRatio"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentInAffiliateActivityLineItems_019e6fc4-5d02-7909-bb7c-9c933a751708" xlink:to="loc_smg_ExchangeableSharesConversionRatio_019e6fc4-5d03-755b-a9eb-33b00108029b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_NumberOfVariableInterestEntityBoardMembers_019e6fc4-5d03-75db-a5f5-793a40ece3d9" xlink:href="smg-20260627.xsd#smg_NumberOfVariableInterestEntityBoardMembers"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentInAffiliateActivityLineItems_019e6fc4-5d02-7909-bb7c-9c933a751708" xlink:to="loc_smg_NumberOfVariableInterestEntityBoardMembers_019e6fc4-5d03-75db-a5f5-793a40ece3d9" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_GainLossOnExchangeOfConvertibleDebtInstrument_019e6fc4-5d03-760b-bf2c-f3c7d09d01a8" xlink:href="smg-20260627.xsd#smg_GainLossOnExchangeOfConvertibleDebtInstrument"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentInAffiliateActivityLineItems_019e6fc4-5d02-7909-bb7c-9c933a751708" xlink:to="loc_smg_GainLossOnExchangeOfConvertibleDebtInstrument_019e6fc4-5d03-760b-bf2c-f3c7d09d01a8" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestments_019e6fc4-5d03-7671-8512-caab12558cc2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityMethodInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentInAffiliateActivityLineItems_019e6fc4-5d02-7909-bb7c-9c933a751708" xlink:to="loc_us-gaap_EquityMethodInvestments_019e6fc4-5d03-7671-8512-caab12558cc2" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_ShareExchangeRatio_019e6fc4-5d03-75bd-98f2-ae986dc52700" xlink:href="smg-20260627.xsd#smg_ShareExchangeRatio"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentInAffiliateActivityLineItems_019e6fc4-5d02-7909-bb7c-9c933a751708" xlink:to="loc_smg_ShareExchangeRatio_019e6fc4-5d03-75bd-98f2-ae986dc52700" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityNoteStockSplitConversionRatio1_019fcd6b-2a53-7b0f-87bd-a1d215c39ee3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquityNoteStockSplitConversionRatio1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InvestmentInAffiliateActivityLineItems_019e6fc4-5d02-7909-bb7c-9c933a751708" xlink:to="loc_us-gaap_StockholdersEquityNoteStockSplitConversionRatio1_019fcd6b-2a53-7b0f-87bd-a1d215c39ee3" xlink:type="arc" order="8"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.scotts.com/role/IMPAIRMENTRESTRUCTURINGANDOTHERImpairmentRestructuringandOtherChargesDetails" xlink:type="simple" xlink:href="smg-20260627.xsd#IMPAIRMENTRESTRUCTURINGANDOTHERImpairmentRestructuringandOtherChargesDetails"/>
  <link:definitionLink xlink:role="http://www.scotts.com/role/IMPAIRMENTRESTRUCTURINGANDOTHERImpairmentRestructuringandOtherChargesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringCostAndReserveLineItems_019e6fc4-5d03-712e-90eb-218b5a1a55e3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestructuringCostAndReserveLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_019e6fc4-5d03-74a3-b02f-6f6ae2c7e433" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfRestructuringAndRelatedCostsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_019e6fc4-5d03-712e-90eb-218b5a1a55e3" xlink:to="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_019e6fc4-5d03-74a3-b02f-6f6ae2c7e433" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementOfIncomeLocationBalanceAxis_019e6fc4-5d03-71b8-a8f9-1c4f2c9b4b60" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementOfIncomeLocationBalanceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_019e6fc4-5d03-74a3-b02f-6f6ae2c7e433" xlink:to="loc_us-gaap_StatementOfIncomeLocationBalanceAxis_019e6fc4-5d03-71b8-a8f9-1c4f2c9b4b60" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringCostAndReserveAxis_019e6fc4-5d03-7c5c-b864-42a9dda4be17" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestructuringCostAndReserveAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_019e6fc4-5d03-74a3-b02f-6f6ae2c7e433" xlink:to="loc_us-gaap_RestructuringCostAndReserveAxis_019e6fc4-5d03-7c5c-b864-42a9dda4be17" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TypeOfRestructuringDomain_019e6fc4-5d03-7c5c-b864-42a9dda4be17_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TypeOfRestructuringDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RestructuringCostAndReserveAxis_019e6fc4-5d03-7c5c-b864-42a9dda4be17" xlink:to="loc_us-gaap_TypeOfRestructuringDomain_019e6fc4-5d03-7c5c-b864-42a9dda4be17_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TypeOfRestructuringDomain_019e6fc4-5d03-7c88-bf9b-153868c7d231" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TypeOfRestructuringDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RestructuringCostAndReserveAxis_019e6fc4-5d03-7c5c-b864-42a9dda4be17" xlink:to="loc_us-gaap_TypeOfRestructuringDomain_019e6fc4-5d03-7c88-bf9b-153868c7d231" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_RestructuringAndOtherChargesMember_019e6fc4-5d03-7720-aca1-b508cca7af6b" xlink:href="smg-20260627.xsd#smg_RestructuringAndOtherChargesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TypeOfRestructuringDomain_019e6fc4-5d03-7c88-bf9b-153868c7d231" xlink:to="loc_smg_RestructuringAndOtherChargesMember_019e6fc4-5d03-7720-aca1-b508cca7af6b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_RightOfUseAssetImpairmentMember_019e6fc4-5d03-771a-a682-6f1627b859b8" xlink:href="smg-20260627.xsd#smg_RightOfUseAssetImpairmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TypeOfRestructuringDomain_019e6fc4-5d03-7c88-bf9b-153868c7d231" xlink:to="loc_smg_RightOfUseAssetImpairmentMember_019e6fc4-5d03-771a-a682-6f1627b859b8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringSettlementAndImpairmentProvisions_019e6fc4-5d03-7d6b-a55b-feba60c4633e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestructuringSettlementAndImpairmentProvisions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_019e6fc4-5d03-712e-90eb-218b5a1a55e3" xlink:to="loc_us-gaap_RestructuringSettlementAndImpairmentProvisions_019e6fc4-5d03-7d6b-a55b-feba60c4633e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_GainLossOnExchangeOfConvertibleDebtInstrument_019e6fc4-5d03-7d4e-ba7b-83c87212cfbf" xlink:href="smg-20260627.xsd#smg_GainLossOnExchangeOfConvertibleDebtInstrument"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_019e6fc4-5d03-712e-90eb-218b5a1a55e3" xlink:to="loc_smg_GainLossOnExchangeOfConvertibleDebtInstrument_019e6fc4-5d03-7d4e-ba7b-83c87212cfbf" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_ImpairmentRestructuringAndOtherRecoveriesChargesContinuingOperations_019e6fc4-5d03-7f3b-b942-49f569d2c6fd" xlink:href="smg-20260627.xsd#smg_ImpairmentRestructuringAndOtherRecoveriesChargesContinuingOperations"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_019e6fc4-5d03-712e-90eb-218b5a1a55e3" xlink:to="loc_smg_ImpairmentRestructuringAndOtherRecoveriesChargesContinuingOperations_019e6fc4-5d03-7f3b-b942-49f569d2c6fd" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleAllowanceForCreditLossNotToSellBeforeRecoveryCreditLossPreviouslyRecordedExpenseReversal_019fabcb-e8a2-7829-af61-87a9ed45e103" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleAllowanceForCreditLossNotToSellBeforeRecoveryCreditLossPreviouslyRecordedExpenseReversal"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_019e6fc4-5d03-712e-90eb-218b5a1a55e3" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleAllowanceForCreditLossNotToSellBeforeRecoveryCreditLossPreviouslyRecordedExpenseReversal_019fabcb-e8a2-7829-af61-87a9ed45e103" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.scotts.com/role/IMPAIRMENTRESTRUCTURINGANDOTHERImpairmentRestructuringandOtherChargesDetails_1" xlink:type="simple" xlink:href="smg-20260627.xsd#IMPAIRMENTRESTRUCTURINGANDOTHERImpairmentRestructuringandOtherChargesDetails_1"/>
  <link:definitionLink xlink:role="http://www.scotts.com/role/IMPAIRMENTRESTRUCTURINGANDOTHERImpairmentRestructuringandOtherChargesDetails_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringCostAndReserveLineItems_019e6fc4-5d03-712e-90eb-218b5a1a55e3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestructuringCostAndReserveLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_019e6fc4-5d03-74a3-b02f-6f6ae2c7e433" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfRestructuringAndRelatedCostsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_019e6fc4-5d03-712e-90eb-218b5a1a55e3" xlink:to="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_019e6fc4-5d03-74a3-b02f-6f6ae2c7e433" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringCostAndReserveAxis_019e6fc4-5d03-7c5c-b864-42a9dda4be17" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestructuringCostAndReserveAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_019e6fc4-5d03-74a3-b02f-6f6ae2c7e433" xlink:to="loc_us-gaap_RestructuringCostAndReserveAxis_019e6fc4-5d03-7c5c-b864-42a9dda4be17" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TypeOfRestructuringDomain_019e6fc4-5d03-7c5c-b864-42a9dda4be17_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TypeOfRestructuringDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RestructuringCostAndReserveAxis_019e6fc4-5d03-7c5c-b864-42a9dda4be17" xlink:to="loc_us-gaap_TypeOfRestructuringDomain_019e6fc4-5d03-7c5c-b864-42a9dda4be17_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TypeOfRestructuringDomain_019e6fc4-5d03-7c88-bf9b-153868c7d231" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TypeOfRestructuringDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RestructuringCostAndReserveAxis_019e6fc4-5d03-7c5c-b864-42a9dda4be17" xlink:to="loc_us-gaap_TypeOfRestructuringDomain_019e6fc4-5d03-7c88-bf9b-153868c7d231" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_RestructuringAndOtherChargesMember_019e6fc4-5d03-7720-aca1-b508cca7af6b" xlink:href="smg-20260627.xsd#smg_RestructuringAndOtherChargesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TypeOfRestructuringDomain_019e6fc4-5d03-7c88-bf9b-153868c7d231" xlink:to="loc_smg_RestructuringAndOtherChargesMember_019e6fc4-5d03-7720-aca1-b508cca7af6b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_RightOfUseAssetImpairmentMember_019e6fc4-5d03-771a-a682-6f1627b859b8" xlink:href="smg-20260627.xsd#smg_RightOfUseAssetImpairmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TypeOfRestructuringDomain_019e6fc4-5d03-7c88-bf9b-153868c7d231" xlink:to="loc_smg_RightOfUseAssetImpairmentMember_019e6fc4-5d03-771a-a682-6f1627b859b8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringSettlementAndImpairmentProvisions_019e6fc4-5d03-7d6b-a55b-feba60c4633e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestructuringSettlementAndImpairmentProvisions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_019e6fc4-5d03-712e-90eb-218b5a1a55e3" xlink:to="loc_us-gaap_RestructuringSettlementAndImpairmentProvisions_019e6fc4-5d03-7d6b-a55b-feba60c4633e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_GainLossOnExchangeOfConvertibleDebtInstrument_019e6fc4-5d03-7d4e-ba7b-83c87212cfbf" xlink:href="smg-20260627.xsd#smg_GainLossOnExchangeOfConvertibleDebtInstrument"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_019e6fc4-5d03-712e-90eb-218b5a1a55e3" xlink:to="loc_smg_GainLossOnExchangeOfConvertibleDebtInstrument_019e6fc4-5d03-7d4e-ba7b-83c87212cfbf" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_ImpairmentRestructuringAndOtherRecoveriesChargesContinuingOperations_019e6fc4-5d03-7f3b-b942-49f569d2c6fd" xlink:href="smg-20260627.xsd#smg_ImpairmentRestructuringAndOtherRecoveriesChargesContinuingOperations"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_019e6fc4-5d03-712e-90eb-218b5a1a55e3" xlink:to="loc_smg_ImpairmentRestructuringAndOtherRecoveriesChargesContinuingOperations_019e6fc4-5d03-7f3b-b942-49f569d2c6fd" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleAllowanceForCreditLossNotToSellBeforeRecoveryCreditLossPreviouslyRecordedExpenseReversal_019fabcb-e8a2-7829-af61-87a9ed45e103" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleAllowanceForCreditLossNotToSellBeforeRecoveryCreditLossPreviouslyRecordedExpenseReversal"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_019e6fc4-5d03-712e-90eb-218b5a1a55e3" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleAllowanceForCreditLossNotToSellBeforeRecoveryCreditLossPreviouslyRecordedExpenseReversal_019fabcb-e8a2-7829-af61-87a9ed45e103" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.scotts.com/role/IMPAIRMENTRESTRUCTURINGANDOTHERNarrativeDetails" xlink:type="simple" xlink:href="smg-20260627.xsd#IMPAIRMENTRESTRUCTURINGANDOTHERNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.scotts.com/role/IMPAIRMENTRESTRUCTURINGANDOTHERNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringCostAndReserveLineItems_019e6fc4-5d03-7c65-8008-7e3221c89bfe" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestructuringCostAndReserveLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_019e6fc4-5d03-7e47-a2d7-ba715b89643d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfRestructuringAndRelatedCostsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_019e6fc4-5d03-7c65-8008-7e3221c89bfe" xlink:to="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_019e6fc4-5d03-7e47-a2d7-ba715b89643d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_019e6fc4-5d03-7437-9200-e456579713c8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_019e6fc4-5d03-7e47-a2d7-ba715b89643d" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_019e6fc4-5d03-7437-9200-e456579713c8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_019e6fc4-5d03-7437-9200-e456579713c8_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_019e6fc4-5d03-7437-9200-e456579713c8" xlink:to="loc_us-gaap_SegmentDomain_019e6fc4-5d03-7437-9200-e456579713c8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_019e6fc4-5d03-7de0-a411-8448e9d8c13a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_019e6fc4-5d03-7437-9200-e456579713c8" xlink:to="loc_us-gaap_SegmentDomain_019e6fc4-5d03-7de0-a411-8448e9d8c13a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_U.S.ConsumerMember_019e6fc4-5d03-7144-949e-081e3d04ef35" xlink:href="smg-20260627.xsd#smg_U.S.ConsumerMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_019e6fc4-5d03-7de0-a411-8448e9d8c13a" xlink:to="loc_smg_U.S.ConsumerMember_019e6fc4-5d03-7144-949e-081e3d04ef35" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateMember_019fc999-fd3a-7cbc-8c0f-ab9ac4c34d30" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CorporateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_019e6fc4-5d03-7de0-a411-8448e9d8c13a" xlink:to="loc_us-gaap_CorporateMember_019fc999-fd3a-7cbc-8c0f-ab9ac4c34d30" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementOfIncomeLocationBalanceAxis_019e6fc4-5d03-7a8d-ba8f-8a271bcfdb6f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementOfIncomeLocationBalanceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_019e6fc4-5d03-7e47-a2d7-ba715b89643d" xlink:to="loc_us-gaap_StatementOfIncomeLocationBalanceAxis_019e6fc4-5d03-7a8d-ba8f-8a271bcfdb6f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_TitleOfIndividualAxis_019fc999-fd3a-7a06-b55e-6cf25ade0610" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_TitleOfIndividualAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_019e6fc4-5d03-7e47-a2d7-ba715b89643d" xlink:to="loc_srt_TitleOfIndividualAxis_019fc999-fd3a-7a06-b55e-6cf25ade0610" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_TitleOfIndividualWithRelationshipToEntityDomain_019fc999-fd3a-7a06-b55e-6cf25ade0610_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_TitleOfIndividualWithRelationshipToEntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_TitleOfIndividualAxis_019fc999-fd3a-7a06-b55e-6cf25ade0610" xlink:to="loc_srt_TitleOfIndividualWithRelationshipToEntityDomain_019fc999-fd3a-7a06-b55e-6cf25ade0610_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_TitleOfIndividualWithRelationshipToEntityDomain_019fc999-fd3a-7e0c-9f10-6950c1d76ada" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_TitleOfIndividualWithRelationshipToEntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_TitleOfIndividualAxis_019fc999-fd3a-7a06-b55e-6cf25ade0610" xlink:to="loc_srt_TitleOfIndividualWithRelationshipToEntityDomain_019fc999-fd3a-7e0c-9f10-6950c1d76ada" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_EmployeesAndExecutivesMember_019fc999-fd3a-7252-a1f5-e7bec0d7c314" xlink:href="smg-20260627.xsd#smg_EmployeesAndExecutivesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_TitleOfIndividualWithRelationshipToEntityDomain_019fc999-fd3a-7e0c-9f10-6950c1d76ada" xlink:to="loc_smg_EmployeesAndExecutivesMember_019fc999-fd3a-7252-a1f5-e7bec0d7c314" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringReserveNoncurrent_019e6fc4-5d03-79dc-9e02-a93ca9de9436" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestructuringReserveNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_019e6fc4-5d03-7c65-8008-7e3221c89bfe" xlink:to="loc_us-gaap_RestructuringReserveNoncurrent_019e6fc4-5d03-79dc-9e02-a93ca9de9436" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeveranceCosts1_019fc999-fd3a-71c1-9e98-7c47ab695505" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SeveranceCosts1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_019e6fc4-5d03-7c65-8008-7e3221c89bfe" xlink:to="loc_us-gaap_SeveranceCosts1_019fc999-fd3a-71c1-9e98-7c47ab695505" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_GainLossOnExchangeOfConvertibleDebtInstrument_019fc99a-3ce6-7c2b-a21b-c23ea5bc7cfb" xlink:href="smg-20260627.xsd#smg_GainLossOnExchangeOfConvertibleDebtInstrument"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_019e6fc4-5d03-7c65-8008-7e3221c89bfe" xlink:to="loc_smg_GainLossOnExchangeOfConvertibleDebtInstrument_019fc99a-3ce6-7c2b-a21b-c23ea5bc7cfb" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProvisionForLoanLossesExpensed_019fcdaf-72e9-719f-8c2b-ca65ef210426" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProvisionForLoanLossesExpensed"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_019e6fc4-5d03-7c65-8008-7e3221c89bfe" xlink:to="loc_us-gaap_ProvisionForLoanLossesExpensed_019fcdaf-72e9-719f-8c2b-ca65ef210426" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProvisionForOtherCreditLosses_019fcdaf-72e9-710b-865a-50c126be223d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProvisionForOtherCreditLosses"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_019e6fc4-5d03-7c65-8008-7e3221c89bfe" xlink:to="loc_us-gaap_ProvisionForOtherCreditLosses_019fcdaf-72e9-710b-865a-50c126be223d" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainLossRelatedToLitigationSettlement_019fcdaf-72e9-7663-ab94-baa1335d4a0e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GainLossRelatedToLitigationSettlement"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_019e6fc4-5d03-7c65-8008-7e3221c89bfe" xlink:to="loc_us-gaap_GainLossRelatedToLitigationSettlement_019fcdaf-72e9-7663-ab94-baa1335d4a0e" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringCosts_019fcdb0-048e-7c82-b659-7ac5f79fcaf7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestructuringCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_019e6fc4-5d03-7c65-8008-7e3221c89bfe" xlink:to="loc_us-gaap_RestructuringCosts_019fcdb0-048e-7c82-b659-7ac5f79fcaf7" xlink:type="arc" order="6"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.scotts.com/role/IMPAIRMENTRESTRUCTURINGANDOTHERNarrativeDetails_1" xlink:type="simple" xlink:href="smg-20260627.xsd#IMPAIRMENTRESTRUCTURINGANDOTHERNarrativeDetails_1"/>
  <link:definitionLink xlink:role="http://www.scotts.com/role/IMPAIRMENTRESTRUCTURINGANDOTHERNarrativeDetails_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringCostAndReserveLineItems_019e6fc4-5d03-7c65-8008-7e3221c89bfe" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestructuringCostAndReserveLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_019e6fc4-5d03-7e47-a2d7-ba715b89643d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfRestructuringAndRelatedCostsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_019e6fc4-5d03-7c65-8008-7e3221c89bfe" xlink:to="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_019e6fc4-5d03-7e47-a2d7-ba715b89643d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_019e6fc4-5d03-7437-9200-e456579713c8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_019e6fc4-5d03-7e47-a2d7-ba715b89643d" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_019e6fc4-5d03-7437-9200-e456579713c8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_019e6fc4-5d03-7437-9200-e456579713c8_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_019e6fc4-5d03-7437-9200-e456579713c8" xlink:to="loc_us-gaap_SegmentDomain_019e6fc4-5d03-7437-9200-e456579713c8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_019e6fc4-5d03-7de0-a411-8448e9d8c13a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_019e6fc4-5d03-7437-9200-e456579713c8" xlink:to="loc_us-gaap_SegmentDomain_019e6fc4-5d03-7de0-a411-8448e9d8c13a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_U.S.ConsumerMember_019e6fc4-5d03-7144-949e-081e3d04ef35" xlink:href="smg-20260627.xsd#smg_U.S.ConsumerMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_019e6fc4-5d03-7de0-a411-8448e9d8c13a" xlink:to="loc_smg_U.S.ConsumerMember_019e6fc4-5d03-7144-949e-081e3d04ef35" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateMember_019fc999-fd3a-7cbc-8c0f-ab9ac4c34d30" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CorporateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_019e6fc4-5d03-7de0-a411-8448e9d8c13a" xlink:to="loc_us-gaap_CorporateMember_019fc999-fd3a-7cbc-8c0f-ab9ac4c34d30" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_TitleOfIndividualAxis_019fc999-fd3a-7a06-b55e-6cf25ade0610" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_TitleOfIndividualAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_019e6fc4-5d03-7e47-a2d7-ba715b89643d" xlink:to="loc_srt_TitleOfIndividualAxis_019fc999-fd3a-7a06-b55e-6cf25ade0610" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_TitleOfIndividualWithRelationshipToEntityDomain_019fc999-fd3a-7a06-b55e-6cf25ade0610_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_TitleOfIndividualWithRelationshipToEntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_TitleOfIndividualAxis_019fc999-fd3a-7a06-b55e-6cf25ade0610" xlink:to="loc_srt_TitleOfIndividualWithRelationshipToEntityDomain_019fc999-fd3a-7a06-b55e-6cf25ade0610_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_TitleOfIndividualWithRelationshipToEntityDomain_019fc999-fd3a-7e0c-9f10-6950c1d76ada" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_TitleOfIndividualWithRelationshipToEntityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_TitleOfIndividualAxis_019fc999-fd3a-7a06-b55e-6cf25ade0610" xlink:to="loc_srt_TitleOfIndividualWithRelationshipToEntityDomain_019fc999-fd3a-7e0c-9f10-6950c1d76ada" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_EmployeesAndExecutivesMember_019fc999-fd3a-7252-a1f5-e7bec0d7c314" xlink:href="smg-20260627.xsd#smg_EmployeesAndExecutivesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_TitleOfIndividualWithRelationshipToEntityDomain_019fc999-fd3a-7e0c-9f10-6950c1d76ada" xlink:to="loc_smg_EmployeesAndExecutivesMember_019fc999-fd3a-7252-a1f5-e7bec0d7c314" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringReserveNoncurrent_019e6fc4-5d03-79dc-9e02-a93ca9de9436" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestructuringReserveNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_019e6fc4-5d03-7c65-8008-7e3221c89bfe" xlink:to="loc_us-gaap_RestructuringReserveNoncurrent_019e6fc4-5d03-79dc-9e02-a93ca9de9436" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeveranceCosts1_019fc999-fd3a-71c1-9e98-7c47ab695505" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SeveranceCosts1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_019e6fc4-5d03-7c65-8008-7e3221c89bfe" xlink:to="loc_us-gaap_SeveranceCosts1_019fc999-fd3a-71c1-9e98-7c47ab695505" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_GainLossOnExchangeOfConvertibleDebtInstrument_019fc99a-3ce6-7c2b-a21b-c23ea5bc7cfb" xlink:href="smg-20260627.xsd#smg_GainLossOnExchangeOfConvertibleDebtInstrument"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_019e6fc4-5d03-7c65-8008-7e3221c89bfe" xlink:to="loc_smg_GainLossOnExchangeOfConvertibleDebtInstrument_019fc99a-3ce6-7c2b-a21b-c23ea5bc7cfb" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProvisionForLoanLossesExpensed_019fcdaf-72e9-719f-8c2b-ca65ef210426" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProvisionForLoanLossesExpensed"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_019e6fc4-5d03-7c65-8008-7e3221c89bfe" xlink:to="loc_us-gaap_ProvisionForLoanLossesExpensed_019fcdaf-72e9-719f-8c2b-ca65ef210426" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProvisionForOtherCreditLosses_019fcdaf-72e9-710b-865a-50c126be223d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProvisionForOtherCreditLosses"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_019e6fc4-5d03-7c65-8008-7e3221c89bfe" xlink:to="loc_us-gaap_ProvisionForOtherCreditLosses_019fcdaf-72e9-710b-865a-50c126be223d" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainLossRelatedToLitigationSettlement_019fcdaf-72e9-7663-ab94-baa1335d4a0e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GainLossRelatedToLitigationSettlement"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_019e6fc4-5d03-7c65-8008-7e3221c89bfe" xlink:to="loc_us-gaap_GainLossRelatedToLitigationSettlement_019fcdaf-72e9-7663-ab94-baa1335d4a0e" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringCosts_019fcdb0-048e-7c82-b659-7ac5f79fcaf7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestructuringCosts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_019e6fc4-5d03-7c65-8008-7e3221c89bfe" xlink:to="loc_us-gaap_RestructuringCosts_019fcdb0-048e-7c82-b659-7ac5f79fcaf7" xlink:type="arc" order="6"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.scotts.com/role/MARKETINGAGREEMENTAdditionalInformationDetails" xlink:type="simple" xlink:href="smg-20260627.xsd#MARKETINGAGREEMENTAdditionalInformationDetails"/>
  <link:definitionLink xlink:role="http://www.scotts.com/role/MARKETINGAGREEMENTAdditionalInformationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_smg_MarketingAgreementLineItems_019e6fc4-5d03-7c95-acda-66072b563ecf" xlink:href="smg-20260627.xsd#smg_MarketingAgreementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_MarketingAgreementTable_019e6fc4-5d03-717f-96fd-6f9c26f07ea6" xlink:href="smg-20260627.xsd#smg_MarketingAgreementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_smg_MarketingAgreementLineItems_019e6fc4-5d03-7c95-acda-66072b563ecf" xlink:to="loc_smg_MarketingAgreementTable_019e6fc4-5d03-717f-96fd-6f9c26f07ea6" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_MarketingAgreementAxis_019e6fc4-5d03-7a54-b8b4-b65e987a1a4e" xlink:href="smg-20260627.xsd#smg_MarketingAgreementAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_smg_MarketingAgreementTable_019e6fc4-5d03-717f-96fd-6f9c26f07ea6" xlink:to="loc_smg_MarketingAgreementAxis_019e6fc4-5d03-7a54-b8b4-b65e987a1a4e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_MarketingAgreementDomain_019e6fc4-5d03-7a54-b8b4-b65e987a1a4e_default" xlink:href="smg-20260627.xsd#smg_MarketingAgreementDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_smg_MarketingAgreementAxis_019e6fc4-5d03-7a54-b8b4-b65e987a1a4e" xlink:to="loc_smg_MarketingAgreementDomain_019e6fc4-5d03-7a54-b8b4-b65e987a1a4e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_MarketingAgreementDomain_019e6fc4-5d03-71a1-8b78-070fde44f4c0" xlink:href="smg-20260627.xsd#smg_MarketingAgreementDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_smg_MarketingAgreementAxis_019e6fc4-5d03-7a54-b8b4-b65e987a1a4e" xlink:to="loc_smg_MarketingAgreementDomain_019e6fc4-5d03-71a1-8b78-070fde44f4c0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_RestatedMarketingAgreementMember_019e6fc4-5d03-78c0-82b6-552a04671036" xlink:href="smg-20260627.xsd#smg_RestatedMarketingAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementDomain_019e6fc4-5d03-71a1-8b78-070fde44f4c0" xlink:to="loc_smg_RestatedMarketingAgreementMember_019e6fc4-5d03-78c0-82b6-552a04671036" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_ThirdRestatedAgreementMember_019e6fc4-5d03-7d1c-a0db-02bd169ee410" xlink:href="smg-20260627.xsd#smg_ThirdRestatedAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementDomain_019e6fc4-5d03-71a1-8b78-070fde44f4c0" xlink:to="loc_smg_ThirdRestatedAgreementMember_019e6fc4-5d03-7d1c-a0db-02bd169ee410" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_CommissionPayablePercentageofProgramEarnings_019e6fc4-5d03-7fa9-8d70-dd328d83c90e" xlink:href="smg-20260627.xsd#smg_CommissionPayablePercentageofProgramEarnings"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementLineItems_019e6fc4-5d03-7c95-acda-66072b563ecf" xlink:to="loc_smg_CommissionPayablePercentageofProgramEarnings_019e6fc4-5d03-7fa9-8d70-dd328d83c90e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_ContractualCommitmentsFutureMinimumPaymentsDue_019e6fc4-5d03-7118-8a17-904a1004a9fe" xlink:href="smg-20260627.xsd#smg_ContractualCommitmentsFutureMinimumPaymentsDue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementLineItems_019e6fc4-5d03-7c95-acda-66072b563ecf" xlink:to="loc_smg_ContractualCommitmentsFutureMinimumPaymentsDue_019e6fc4-5d03-7118-8a17-904a1004a9fe" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_ProgramAgreementTermsMinimumAnnualEBITRequiredToAvoidReductionOfContributionPayment_019e6fc4-5d03-7a79-b604-46238a51750d" xlink:href="smg-20260627.xsd#smg_ProgramAgreementTermsMinimumAnnualEBITRequiredToAvoidReductionOfContributionPayment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementLineItems_019e6fc4-5d03-7c95-acda-66072b563ecf" xlink:to="loc_smg_ProgramAgreementTermsMinimumAnnualEBITRequiredToAvoidReductionOfContributionPayment_019e6fc4-5d03-7a79-b604-46238a51750d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_MarketingAgreementTermsMinimumEarningsBeforeIncomeTaxes_019e6fc4-5d03-772b-8020-4f7e0c12acfd" xlink:href="smg-20260627.xsd#smg_MarketingAgreementTermsMinimumEarningsBeforeIncomeTaxes"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementLineItems_019e6fc4-5d03-7c95-acda-66072b563ecf" xlink:to="loc_smg_MarketingAgreementTermsMinimumEarningsBeforeIncomeTaxes_019e6fc4-5d03-772b-8020-4f7e0c12acfd" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_BrandDecommisioningEventPayable_019e6fc4-5d03-72cc-8c82-d947f281c90d" xlink:href="smg-20260627.xsd#smg_BrandDecommisioningEventPayable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementLineItems_019e6fc4-5d03-7c95-acda-66072b563ecf" xlink:to="loc_smg_BrandDecommisioningEventPayable_019e6fc4-5d03-72cc-8c82-d947f281c90d" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_MinimumTerminationFeePayable_019e6fc4-5d03-724c-b1a1-f96155345922" xlink:href="smg-20260627.xsd#smg_MinimumTerminationFeePayable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementLineItems_019e6fc4-5d03-7c95-acda-66072b563ecf" xlink:to="loc_smg_MinimumTerminationFeePayable_019e6fc4-5d03-724c-b1a1-f96155345922" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_MinimumTerminationFeePayableMultipleofAverageProgramEarningsPrior3Years_019e6fc4-5d03-779b-ba22-f8cf04c3ec64" xlink:href="smg-20260627.xsd#smg_MinimumTerminationFeePayableMultipleofAverageProgramEarningsPrior3Years"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementLineItems_019e6fc4-5d03-7c95-acda-66072b563ecf" xlink:to="loc_smg_MinimumTerminationFeePayableMultipleofAverageProgramEarningsPrior3Years_019e6fc4-5d03-779b-ba22-f8cf04c3ec64" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_MinimumTerminationFeePayableThreshold_019e6fc4-5d03-76c4-b608-96debfa8b0c8" xlink:href="smg-20260627.xsd#smg_MinimumTerminationFeePayableThreshold"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementLineItems_019e6fc4-5d03-7c95-acda-66072b563ecf" xlink:to="loc_smg_MinimumTerminationFeePayableThreshold_019e6fc4-5d03-76c4-b608-96debfa8b0c8" xlink:type="arc" order="7"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.scotts.com/role/MARKETINGAGREEMENTNetCommissionEarnedUnderMarketingAgreementDetails" xlink:type="simple" xlink:href="smg-20260627.xsd#MARKETINGAGREEMENTNetCommissionEarnedUnderMarketingAgreementDetails"/>
  <link:definitionLink xlink:role="http://www.scotts.com/role/MARKETINGAGREEMENTNetCommissionEarnedUnderMarketingAgreementDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_smg_MarketingAgreementLineItems_019e6fc4-5d03-78f1-a947-965951b74f50" xlink:href="smg-20260627.xsd#smg_MarketingAgreementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_MarketingAgreementTable_019e6fc4-5d03-7e5e-9136-11411cdfdd68" xlink:href="smg-20260627.xsd#smg_MarketingAgreementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_smg_MarketingAgreementLineItems_019e6fc4-5d03-78f1-a947-965951b74f50" xlink:to="loc_smg_MarketingAgreementTable_019e6fc4-5d03-7e5e-9136-11411cdfdd68" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_MarketingAgreementAxis_019e6fc4-5d03-7fa7-b9b3-b3549cc6bda2" xlink:href="smg-20260627.xsd#smg_MarketingAgreementAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_smg_MarketingAgreementTable_019e6fc4-5d03-7e5e-9136-11411cdfdd68" xlink:to="loc_smg_MarketingAgreementAxis_019e6fc4-5d03-7fa7-b9b3-b3549cc6bda2" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_MarketingAgreementDomain_019e6fc4-5d03-7fa7-b9b3-b3549cc6bda2_default" xlink:href="smg-20260627.xsd#smg_MarketingAgreementDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_smg_MarketingAgreementAxis_019e6fc4-5d03-7fa7-b9b3-b3549cc6bda2" xlink:to="loc_smg_MarketingAgreementDomain_019e6fc4-5d03-7fa7-b9b3-b3549cc6bda2_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_MarketingAgreementDomain_019e6fc4-5d03-7e1e-9b99-5254b56bfc37" xlink:href="smg-20260627.xsd#smg_MarketingAgreementDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_smg_MarketingAgreementAxis_019e6fc4-5d03-7fa7-b9b3-b3549cc6bda2" xlink:to="loc_smg_MarketingAgreementDomain_019e6fc4-5d03-7e1e-9b99-5254b56bfc37" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_RestatedMarketingAgreementMember_019e6fc4-5d03-7d17-9fdd-ff17bd89c8eb" xlink:href="smg-20260627.xsd#smg_RestatedMarketingAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementDomain_019e6fc4-5d03-7e1e-9b99-5254b56bfc37" xlink:to="loc_smg_RestatedMarketingAgreementMember_019e6fc4-5d03-7d17-9fdd-ff17bd89c8eb" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_CommissionIncomeGross_019e6fc4-5d03-7572-9f5c-75ad05963aeb" xlink:href="smg-20260627.xsd#smg_CommissionIncomeGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementLineItems_019e6fc4-5d03-78f1-a947-965951b74f50" xlink:to="loc_smg_CommissionIncomeGross_019e6fc4-5d03-7572-9f5c-75ad05963aeb" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CostOfGoodsAndServicesSold_019e6fc4-5d03-7080-8930-c74f2ae39899" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CostOfGoodsAndServicesSold"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementLineItems_019e6fc4-5d03-78f1-a947-965951b74f50" xlink:to="loc_us-gaap_CostOfGoodsAndServicesSold_019e6fc4-5d03-7080-8930-c74f2ae39899" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_CommissionIncomeExpenseNet_019e6fc4-5d03-7d99-bbdc-5db738bf9fa3" xlink:href="smg-20260627.xsd#smg_CommissionIncomeExpenseNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementLineItems_019e6fc4-5d03-78f1-a947-965951b74f50" xlink:to="loc_smg_CommissionIncomeExpenseNet_019e6fc4-5d03-7d99-bbdc-5db738bf9fa3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_RevenuesReimbursementMarketingAgreement_019e6fc4-5d03-7e45-8ddd-950e23dd8f8e" xlink:href="smg-20260627.xsd#smg_RevenuesReimbursementMarketingAgreement"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementLineItems_019e6fc4-5d03-78f1-a947-965951b74f50" xlink:to="loc_smg_RevenuesReimbursementMarketingAgreement_019e6fc4-5d03-7e45-8ddd-950e23dd8f8e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_NetSalesWithAgencyAgreement_019e6fc4-5d03-7708-b4db-d1ee0083d353" xlink:href="smg-20260627.xsd#smg_NetSalesWithAgencyAgreement"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_smg_MarketingAgreementLineItems_019e6fc4-5d03-78f1-a947-965951b74f50" xlink:to="loc_smg_NetSalesWithAgencyAgreement_019e6fc4-5d03-7708-b4db-d1ee0083d353" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.scotts.com/role/DEBTComponentsofLongTermDebtDetails" xlink:type="simple" xlink:href="smg-20260627.xsd#DEBTComponentsofLongTermDebtDetails"/>
  <link:definitionLink xlink:role="http://www.scotts.com/role/DEBTComponentsofLongTermDebtDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentLineItems_019e6fc4-5d03-7722-8fa4-c5adfe0f3eda" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTable_019e6fc4-5d03-7427-a0d7-6f821941fbb1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e6fc4-5d03-7722-8fa4-c5adfe0f3eda" xlink:to="loc_us-gaap_DebtInstrumentTable_019e6fc4-5d03-7427-a0d7-6f821941fbb1" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_019e6fc4-5d03-7ccc-9745-693fb0878a01" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_019e6fc4-5d03-7427-a0d7-6f821941fbb1" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_019e6fc4-5d03-7ccc-9745-693fb0878a01" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019e6fc4-5d03-7ccc-9745-693fb0878a01_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_019e6fc4-5d03-7ccc-9745-693fb0878a01" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019e6fc4-5d03-7ccc-9745-693fb0878a01_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019e6fc4-5d03-79f7-ac3f-2e7826328825" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_019e6fc4-5d03-7ccc-9745-693fb0878a01" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019e6fc4-5d03-79f7-ac3f-2e7826328825" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditMember_019e6fc4-5d03-7bf6-bdd2-9a436037d188" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_019e6fc4-5d03-79f7-ac3f-2e7826328825" xlink:to="loc_us-gaap_LineOfCreditMember_019e6fc4-5d03-7bf6-bdd2-9a436037d188" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeniorNotesMember_019e6fc4-5d03-7614-9365-8709f08f0a15" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SeniorNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_019e6fc4-5d03-79f7-ac3f-2e7826328825" xlink:to="loc_us-gaap_SeniorNotesMember_019e6fc4-5d03-7614-9365-8709f08f0a15" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtMember_019e6fc4-5d03-73e1-ba9d-13e92b40cf97" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_019e6fc4-5d03-79f7-ac3f-2e7826328825" xlink:to="loc_us-gaap_LongTermDebtMember_019e6fc4-5d03-73e1-ba9d-13e92b40cf97" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_DebtOtherMember_019e6fc4-5d03-722a-a4ad-b029576db3cc" xlink:href="smg-20260627.xsd#smg_DebtOtherMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_019e6fc4-5d03-79f7-ac3f-2e7826328825" xlink:to="loc_smg_DebtOtherMember_019e6fc4-5d03-722a-a4ad-b029576db3cc" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ObligationsMember_019e6fc4-5d03-72dc-8670-28717a97d68c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ObligationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_019e6fc4-5d03-79f7-ac3f-2e7826328825" xlink:to="loc_us-gaap_ObligationsMember_019e6fc4-5d03-72dc-8670-28717a97d68c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityAxis_019e6fc4-5d03-7633-b744-4789f945e3f3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_019e6fc4-5d03-7427-a0d7-6f821941fbb1" xlink:to="loc_us-gaap_CreditFacilityAxis_019e6fc4-5d03-7633-b744-4789f945e3f3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_019e6fc4-5d03-7633-b744-4789f945e3f3_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditFacilityAxis_019e6fc4-5d03-7633-b744-4789f945e3f3" xlink:to="loc_us-gaap_CreditFacilityDomain_019e6fc4-5d03-7633-b744-4789f945e3f3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_019e6fc4-5d03-7d18-8a0b-6255a4829b8d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditFacilityAxis_019e6fc4-5d03-7633-b744-4789f945e3f3" xlink:to="loc_us-gaap_CreditFacilityDomain_019e6fc4-5d03-7d18-8a0b-6255a4829b8d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevolvingCreditFacilityMember_019e6fc4-5d03-7a62-8fd1-7e640feba15d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevolvingCreditFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_019e6fc4-5d03-7d18-8a0b-6255a4829b8d" xlink:to="loc_us-gaap_RevolvingCreditFacilityMember_019e6fc4-5d03-7a62-8fd1-7e640feba15d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_TermLoanMember_019e6fc4-5d03-733f-aff2-1d624f47b54c" xlink:href="smg-20260627.xsd#smg_TermLoanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_019e6fc4-5d03-7d18-8a0b-6255a4829b8d" xlink:to="loc_smg_TermLoanMember_019e6fc4-5d03-733f-aff2-1d624f47b54c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_019e6fc4-5d03-7381-8b03-aae213b5d4d2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_019e6fc4-5d03-7427-a0d7-6f821941fbb1" xlink:to="loc_us-gaap_DebtInstrumentAxis_019e6fc4-5d03-7381-8b03-aae213b5d4d2" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019e6fc4-5d03-7381-8b03-aae213b5d4d2_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_019e6fc4-5d03-7381-8b03-aae213b5d4d2" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019e6fc4-5d03-7381-8b03-aae213b5d4d2_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019e6fc4-5d03-7987-b1aa-f368bc79d5be" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_019e6fc4-5d03-7381-8b03-aae213b5d4d2" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019e6fc4-5d03-7987-b1aa-f368bc79d5be" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_A4000SeniorNotesMember_019e6fc4-5d03-7c36-ad37-a7a6d6dec4f2" xlink:href="smg-20260627.xsd#smg_A4000SeniorNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019e6fc4-5d03-7987-b1aa-f368bc79d5be" xlink:to="loc_smg_A4000SeniorNotesMember_019e6fc4-5d03-7c36-ad37-a7a6d6dec4f2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_A4375SeniorNotesMember_019e6fc4-5d03-76cf-9dfc-818dd0f2eeec" xlink:href="smg-20260627.xsd#smg_A4375SeniorNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019e6fc4-5d03-7987-b1aa-f368bc79d5be" xlink:to="loc_smg_A4375SeniorNotesMember_019e6fc4-5d03-76cf-9dfc-818dd0f2eeec" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_A4500SeniorNotesMember_019e6fc4-5d03-7017-82a7-59165177281d" xlink:href="smg-20260627.xsd#smg_A4500SeniorNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019e6fc4-5d03-7987-b1aa-f368bc79d5be" xlink:to="loc_smg_A4500SeniorNotesMember_019e6fc4-5d03-7017-82a7-59165177281d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_A5250SeniorNotesMember_019e6fc4-5d03-7627-aa2f-61549b50d8c4" xlink:href="smg-20260627.xsd#smg_A5250SeniorNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019e6fc4-5d03-7987-b1aa-f368bc79d5be" xlink:to="loc_smg_A5250SeniorNotesMember_019e6fc4-5d03-7627-aa2f-61549b50d8c4" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_019e6fc4-5d03-7b43-bc1c-f79809b84331" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e6fc4-5d03-7722-8fa4-c5adfe0f3eda" xlink:to="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_019e6fc4-5d03-7b43-bc1c-f79809b84331" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentCarryingAmount_019e6fc4-5d03-7d45-b1e0-73e7dde895e1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentCarryingAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e6fc4-5d03-7722-8fa4-c5adfe0f3eda" xlink:to="loc_us-gaap_DebtInstrumentCarryingAmount_019e6fc4-5d03-7d45-b1e0-73e7dde895e1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtCurrent_019e6fc4-5d03-7c47-8a6e-4431759f9807" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e6fc4-5d03-7722-8fa4-c5adfe0f3eda" xlink:to="loc_us-gaap_LongTermDebtCurrent_019e6fc4-5d03-7c47-8a6e-4431759f9807" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnamortizedDebtIssuanceExpense_019e6fc4-5d03-75ac-862c-6d4f421cf088" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_UnamortizedDebtIssuanceExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e6fc4-5d03-7722-8fa4-c5adfe0f3eda" xlink:to="loc_us-gaap_UnamortizedDebtIssuanceExpense_019e6fc4-5d03-75ac-862c-6d4f421cf088" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtNoncurrent_019e6fc4-5d03-7a63-8278-7bf9bfc82d6a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtNoncurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e6fc4-5d03-7722-8fa4-c5adfe0f3eda" xlink:to="loc_us-gaap_LongTermDebtNoncurrent_019e6fc4-5d03-7a63-8278-7bf9bfc82d6a" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.scotts.com/role/DEBTCreditFacilitiesDetails" xlink:type="simple" xlink:href="smg-20260627.xsd#DEBTCreditFacilitiesDetails"/>
  <link:definitionLink xlink:role="http://www.scotts.com/role/DEBTCreditFacilitiesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentLineItems_019e6fc4-5d03-7362-acbc-700af01aa791" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTable_019e6fc4-5d03-71c0-a579-b01ef08b8300" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e6fc4-5d03-7362-acbc-700af01aa791" xlink:to="loc_us-gaap_DebtInstrumentTable_019e6fc4-5d03-71c0-a579-b01ef08b8300" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_019e6fc4-5d03-7830-814f-b15453081a05" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_019e6fc4-5d03-71c0-a579-b01ef08b8300" xlink:to="loc_us-gaap_DebtInstrumentAxis_019e6fc4-5d03-7830-814f-b15453081a05" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019e6fc4-5d03-7830-814f-b15453081a05_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_019e6fc4-5d03-7830-814f-b15453081a05" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019e6fc4-5d03-7830-814f-b15453081a05_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019e6fc4-5d03-7eee-bdac-195f46aa6a76" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_019e6fc4-5d03-7830-814f-b15453081a05" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019e6fc4-5d03-7eee-bdac-195f46aa6a76" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_SeventhAmendedAndRestatedSeniorSecuredCreditAgreementMember_019e6fc4-5d03-719c-9d4e-58300efbc712" xlink:href="smg-20260627.xsd#smg_SeventhAmendedAndRestatedSeniorSecuredCreditAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019e6fc4-5d03-7eee-bdac-195f46aa6a76" xlink:to="loc_smg_SeventhAmendedAndRestatedSeniorSecuredCreditAgreementMember_019e6fc4-5d03-719c-9d4e-58300efbc712" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_019e6fc4-5d03-7612-baf7-d86507645d20" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_019e6fc4-5d03-71c0-a579-b01ef08b8300" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_019e6fc4-5d03-7612-baf7-d86507645d20" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019e6fc4-5d03-7612-baf7-d86507645d20_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_019e6fc4-5d03-7612-baf7-d86507645d20" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019e6fc4-5d03-7612-baf7-d86507645d20_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019e6fc4-5d03-7558-9cba-d6573dd24e3f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_019e6fc4-5d03-7612-baf7-d86507645d20" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019e6fc4-5d03-7558-9cba-d6573dd24e3f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditMember_019e6fc4-5d03-70cd-a171-e63dc8ff4cae" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_019e6fc4-5d03-7558-9cba-d6573dd24e3f" xlink:to="loc_us-gaap_LineOfCreditMember_019e6fc4-5d03-70cd-a171-e63dc8ff4cae" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeniorNotesMember_019e6fc4-5d03-7a3a-8b29-d4d5a3d22686" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SeniorNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_019e6fc4-5d03-7558-9cba-d6573dd24e3f" xlink:to="loc_us-gaap_SeniorNotesMember_019e6fc4-5d03-7a3a-8b29-d4d5a3d22686" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityAxis_019e6fc4-5d03-7a7d-a692-e19c8228ae32" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_019e6fc4-5d03-71c0-a579-b01ef08b8300" xlink:to="loc_us-gaap_CreditFacilityAxis_019e6fc4-5d03-7a7d-a692-e19c8228ae32" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_019e6fc4-5d03-7a7d-a692-e19c8228ae32_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditFacilityAxis_019e6fc4-5d03-7a7d-a692-e19c8228ae32" xlink:to="loc_us-gaap_CreditFacilityDomain_019e6fc4-5d03-7a7d-a692-e19c8228ae32_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_019e6fc4-5d03-7785-9183-71be69c88854" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditFacilityAxis_019e6fc4-5d03-7a7d-a692-e19c8228ae32" xlink:to="loc_us-gaap_CreditFacilityDomain_019e6fc4-5d03-7785-9183-71be69c88854" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevolvingCreditFacilityMember_019e6fc4-5d03-7e1c-8a9b-93fcd51be75e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevolvingCreditFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_019e6fc4-5d03-7785-9183-71be69c88854" xlink:to="loc_us-gaap_RevolvingCreditFacilityMember_019e6fc4-5d03-7e1c-8a9b-93fcd51be75e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_TermLoanMember_019e6fc4-5d03-74a7-846f-9abcf235dc91" xlink:href="smg-20260627.xsd#smg_TermLoanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_019e6fc4-5d03-7785-9183-71be69c88854" xlink:to="loc_smg_TermLoanMember_019e6fc4-5d03-74a7-846f-9abcf235dc91" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LetterOfCreditMember_019e6fc4-5d03-77b1-94bf-dab4c9ce0580" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LetterOfCreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_019e6fc4-5d03-7785-9183-71be69c88854" xlink:to="loc_us-gaap_LetterOfCreditMember_019e6fc4-5d03-77b1-94bf-dab4c9ce0580" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementScenarioAxis_019e6fc4-5d03-728e-bd33-32194efbc168" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_StatementScenarioAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_019e6fc4-5d03-71c0-a579-b01ef08b8300" xlink:to="loc_srt_StatementScenarioAxis_019e6fc4-5d03-728e-bd33-32194efbc168" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScenarioUnspecifiedDomain_019e6fc4-5d03-728e-bd33-32194efbc168_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ScenarioUnspecifiedDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementScenarioAxis_019e6fc4-5d03-728e-bd33-32194efbc168" xlink:to="loc_srt_ScenarioUnspecifiedDomain_019e6fc4-5d03-728e-bd33-32194efbc168_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScenarioUnspecifiedDomain_019e6fc4-5d03-77cd-82f0-49a665c5f4ed" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ScenarioUnspecifiedDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementScenarioAxis_019e6fc4-5d03-728e-bd33-32194efbc168" xlink:to="loc_srt_ScenarioUnspecifiedDomain_019e6fc4-5d03-77cd-82f0-49a665c5f4ed" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ScenarioForecastMember_019e6fc4-5d03-7377-8b05-53126f576c12" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ScenarioForecastMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ScenarioUnspecifiedDomain_019e6fc4-5d03-77cd-82f0-49a665c5f4ed" xlink:to="loc_srt_ScenarioForecastMember_019e6fc4-5d03-7377-8b05-53126f576c12" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_DebtMaturityPeriod_019e6fc4-5d03-7a71-91c7-bd81676d878a" xlink:href="smg-20260627.xsd#smg_DebtMaturityPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e6fc4-5d03-7362-acbc-700af01aa791" xlink:to="loc_smg_DebtMaturityPeriod_019e6fc4-5d03-7a71-91c7-bd81676d878a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_019e6fc4-5d03-738c-b921-881308a41740" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e6fc4-5d03-7362-acbc-700af01aa791" xlink:to="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_019e6fc4-5d03-738c-b921-881308a41740" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_LineOfCreditFacilityAccordionFeatureIncreaseLimit_019e6fc4-5d03-7b37-81ba-3a64513db2f6" xlink:href="smg-20260627.xsd#smg_LineOfCreditFacilityAccordionFeatureIncreaseLimit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e6fc4-5d03-7362-acbc-700af01aa791" xlink:to="loc_smg_LineOfCreditFacilityAccordionFeatureIncreaseLimit_019e6fc4-5d03-7b37-81ba-3a64513db2f6" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCredit_019e6fc4-5d03-7aa2-937b-3592e08fa7b2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCredit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e6fc4-5d03-7362-acbc-700af01aa791" xlink:to="loc_us-gaap_LineOfCredit_019e6fc4-5d03-7aa2-937b-3592e08fa7b2" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity_019e6fc4-5d03-7f0f-b4d7-d932fd0079d8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e6fc4-5d03-7362-acbc-700af01aa791" xlink:to="loc_us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity_019e6fc4-5d03-7f0f-b4d7-d932fd0079d8" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtWeightedAverageInterestRate_019e6fc4-5d03-7536-a634-e17172045e21" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtWeightedAverageInterestRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e6fc4-5d03-7362-acbc-700af01aa791" xlink:to="loc_us-gaap_DebtWeightedAverageInterestRate_019e6fc4-5d03-7536-a634-e17172045e21" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_DebtInstrumentCovenantLeverageRatioMaximum_019e6fc4-5d03-7f4f-91a1-d1358feca227" xlink:href="smg-20260627.xsd#smg_DebtInstrumentCovenantLeverageRatioMaximum"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e6fc4-5d03-7362-acbc-700af01aa791" xlink:to="loc_smg_DebtInstrumentCovenantLeverageRatioMaximum_019e6fc4-5d03-7f4f-91a1-d1358feca227" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_DebtInstrumentCovenantLeverageRatio_019e6fc4-5d03-7f83-b479-901a96a0f30a" xlink:href="smg-20260627.xsd#smg_DebtInstrumentCovenantLeverageRatio"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e6fc4-5d03-7362-acbc-700af01aa791" xlink:to="loc_smg_DebtInstrumentCovenantLeverageRatio_019e6fc4-5d03-7f83-b479-901a96a0f30a" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_DebtInstrumentCovenantInterestCoverageRatioMinimum_019e6fc4-5d03-7a75-b969-47020ed26549" xlink:href="smg-20260627.xsd#smg_DebtInstrumentCovenantInterestCoverageRatioMinimum"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e6fc4-5d03-7362-acbc-700af01aa791" xlink:to="loc_smg_DebtInstrumentCovenantInterestCoverageRatioMinimum_019e6fc4-5d03-7a75-b969-47020ed26549" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_DebtInstrumentCovenantInterestCoverageRatio_019e6fc4-5d03-764d-8e08-e57a0f0eee7b" xlink:href="smg-20260627.xsd#smg_DebtInstrumentCovenantInterestCoverageRatio"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e6fc4-5d03-7362-acbc-700af01aa791" xlink:to="loc_smg_DebtInstrumentCovenantInterestCoverageRatio_019e6fc4-5d03-764d-8e08-e57a0f0eee7b" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_DebtInstrumentCovenantLeverageRatioRestrictedPayments_019e6fc4-5d03-7fe9-8469-93f2f4da45f6" xlink:href="smg-20260627.xsd#smg_DebtInstrumentCovenantLeverageRatioRestrictedPayments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e6fc4-5d03-7362-acbc-700af01aa791" xlink:to="loc_smg_DebtInstrumentCovenantLeverageRatioRestrictedPayments_019e6fc4-5d03-7fe9-8469-93f2f4da45f6" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_DebtInstrumentCovenantAnnualRestrictedPaymentAmountMaximumIfLeverageThresholdExceeded_019e6fc4-5d03-7599-8a4f-19e850fc8669" xlink:href="smg-20260627.xsd#smg_DebtInstrumentCovenantAnnualRestrictedPaymentAmountMaximumIfLeverageThresholdExceeded"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e6fc4-5d03-7362-acbc-700af01aa791" xlink:to="loc_smg_DebtInstrumentCovenantAnnualRestrictedPaymentAmountMaximumIfLeverageThresholdExceeded_019e6fc4-5d03-7599-8a4f-19e850fc8669" xlink:type="arc" order="11"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.scotts.com/role/DEBTSeniorNotesDetails" xlink:type="simple" xlink:href="smg-20260627.xsd#DEBTSeniorNotesDetails"/>
  <link:definitionLink xlink:role="http://www.scotts.com/role/DEBTSeniorNotesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentLineItems_019e6fc4-5d03-7b74-95ca-228396f1c835" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTable_019e6fc4-5d03-7c16-9eb0-511e62f0842e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e6fc4-5d03-7b74-95ca-228396f1c835" xlink:to="loc_us-gaap_DebtInstrumentTable_019e6fc4-5d03-7c16-9eb0-511e62f0842e" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_019e6fc4-5d03-70a3-a395-771571b55949" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_019e6fc4-5d03-7c16-9eb0-511e62f0842e" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_019e6fc4-5d03-70a3-a395-771571b55949" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019e6fc4-5d03-70a3-a395-771571b55949_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_019e6fc4-5d03-70a3-a395-771571b55949" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019e6fc4-5d03-70a3-a395-771571b55949_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019e6fc4-5d03-7634-bdf4-c3f8ff8a4143" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_019e6fc4-5d03-70a3-a395-771571b55949" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019e6fc4-5d03-7634-bdf4-c3f8ff8a4143" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeniorNotesMember_019e6fc4-5d03-7708-92a9-849e43a350f6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SeniorNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_019e6fc4-5d03-7634-bdf4-c3f8ff8a4143" xlink:to="loc_us-gaap_SeniorNotesMember_019e6fc4-5d03-7708-92a9-849e43a350f6" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_019e6fc4-5d03-725f-8712-933bdfea8b64" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DebtInstrumentTable_019e6fc4-5d03-7c16-9eb0-511e62f0842e" xlink:to="loc_us-gaap_DebtInstrumentAxis_019e6fc4-5d03-725f-8712-933bdfea8b64" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019e6fc4-5d03-725f-8712-933bdfea8b64_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_019e6fc4-5d03-725f-8712-933bdfea8b64" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019e6fc4-5d03-725f-8712-933bdfea8b64_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019e6fc4-5d03-7027-b72b-90f175b86fb1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_019e6fc4-5d03-725f-8712-933bdfea8b64" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019e6fc4-5d03-7027-b72b-90f175b86fb1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_A5250SeniorNotesMember_019e6fc4-5d03-7290-a5b4-198e3344be54" xlink:href="smg-20260627.xsd#smg_A5250SeniorNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019e6fc4-5d03-7027-b72b-90f175b86fb1" xlink:to="loc_smg_A5250SeniorNotesMember_019e6fc4-5d03-7290-a5b4-198e3344be54" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_A4500SeniorNotesMember_019e6fc4-5d03-7e26-9c90-d965aa90eae6" xlink:href="smg-20260627.xsd#smg_A4500SeniorNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019e6fc4-5d03-7027-b72b-90f175b86fb1" xlink:to="loc_smg_A4500SeniorNotesMember_019e6fc4-5d03-7e26-9c90-d965aa90eae6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_A4000SeniorNotesMember_019e6fc4-5d03-7872-87d7-d925c01e43a3" xlink:href="smg-20260627.xsd#smg_A4000SeniorNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019e6fc4-5d03-7027-b72b-90f175b86fb1" xlink:to="loc_smg_A4000SeniorNotesMember_019e6fc4-5d03-7872-87d7-d925c01e43a3" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_A4375SeniorNotesMember_019e6fc4-5d03-7421-bbe1-10d736acfe0d" xlink:href="smg-20260627.xsd#smg_A4375SeniorNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019e6fc4-5d03-7027-b72b-90f175b86fb1" xlink:to="loc_smg_A4375SeniorNotesMember_019e6fc4-5d03-7421-bbe1-10d736acfe0d" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_019e6fc4-5d03-7d61-8517-9c910c6cd5d2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e6fc4-5d03-7b74-95ca-228396f1c835" xlink:to="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_019e6fc4-5d03-7d61-8517-9c910c6cd5d2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfUnsecuredDebt_019e6fc4-5d03-7a25-9dec-00ac64554ac5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromIssuanceOfUnsecuredDebt"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e6fc4-5d03-7b74-95ca-228396f1c835" xlink:to="loc_us-gaap_ProceedsFromIssuanceOfUnsecuredDebt_019e6fc4-5d03-7a25-9dec-00ac64554ac5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentFaceAmount_019e6fc4-5d03-724b-b37d-e3cbf3322c23" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentFaceAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e6fc4-5d03-7b74-95ca-228396f1c835" xlink:to="loc_us-gaap_DebtInstrumentFaceAmount_019e6fc4-5d03-724b-b37d-e3cbf3322c23" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_DebtInstrumentCovenantInterestCoverageRatioMinimum_019e6fc4-5d03-76d9-8904-831ce1ca569b" xlink:href="smg-20260627.xsd#smg_DebtInstrumentCovenantInterestCoverageRatioMinimum"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e6fc4-5d03-7b74-95ca-228396f1c835" xlink:to="loc_smg_DebtInstrumentCovenantInterestCoverageRatioMinimum_019e6fc4-5d03-76d9-8904-831ce1ca569b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_DebtInstrumentCovenantInterestCoverageRatio_019e6fc4-5d03-7a55-b857-349a21397287" xlink:href="smg-20260627.xsd#smg_DebtInstrumentCovenantInterestCoverageRatio"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentLineItems_019e6fc4-5d03-7b74-95ca-228396f1c835" xlink:to="loc_smg_DebtInstrumentCovenantInterestCoverageRatio_019e6fc4-5d03-7a55-b857-349a21397287" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.scotts.com/role/DEBTInterestRateSwapAgreementsDetails" xlink:type="simple" xlink:href="smg-20260627.xsd#DEBTInterestRateSwapAgreementsDetails"/>
  <link:definitionLink xlink:role="http://www.scotts.com/role/DEBTInterestRateSwapAgreementsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLineItems_019e6fc4-5d03-7c01-9e81-1e8754b04c1c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeTable_019e6fc4-5d03-7a09-b158-b7b418687f37" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeLineItems_019e6fc4-5d03-7c01-9e81-1e8754b04c1c" xlink:to="loc_us-gaap_DerivativeTable_019e6fc4-5d03-7a09-b158-b7b418687f37" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationAxis_019e6fc4-5d03-70d0-bb0a-40fcd984dc22" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgingDesignationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_019e6fc4-5d03-7a09-b158-b7b418687f37" xlink:to="loc_us-gaap_HedgingDesignationAxis_019e6fc4-5d03-70d0-bb0a-40fcd984dc22" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationDomain_019e6fc4-5d03-70d0-bb0a-40fcd984dc22_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgingDesignationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_HedgingDesignationAxis_019e6fc4-5d03-70d0-bb0a-40fcd984dc22" xlink:to="loc_us-gaap_HedgingDesignationDomain_019e6fc4-5d03-70d0-bb0a-40fcd984dc22_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationDomain_019e6fc4-5d03-7723-8e04-8f2d79192d70" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgingDesignationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_HedgingDesignationAxis_019e6fc4-5d03-70d0-bb0a-40fcd984dc22" xlink:to="loc_us-gaap_HedgingDesignationDomain_019e6fc4-5d03-7723-8e04-8f2d79192d70" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DesignatedAsHedgingInstrumentMember_019e6fc4-5d03-7a43-8d96-c1fa78d91611" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DesignatedAsHedgingInstrumentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingDesignationDomain_019e6fc4-5d03-7723-8e04-8f2d79192d70" xlink:to="loc_us-gaap_DesignatedAsHedgingInstrumentMember_019e6fc4-5d03-7a43-8d96-c1fa78d91611" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6fc4-5d03-7659-8d72-c99062aa974e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_019e6fc4-5d03-7a09-b158-b7b418687f37" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6fc4-5d03-7659-8d72-c99062aa974e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019e6fc4-5d03-7659-8d72-c99062aa974e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6fc4-5d03-7659-8d72-c99062aa974e" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019e6fc4-5d03-7659-8d72-c99062aa974e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019e6fc4-5d03-7378-8cfa-82a18cfea902" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6fc4-5d03-7659-8d72-c99062aa974e" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019e6fc4-5d03-7378-8cfa-82a18cfea902" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateSwapMember_019e6fc4-5d03-74c3-9294-83fcedd90df9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestRateSwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6fc4-5d03-7378-8cfa-82a18cfea902" xlink:to="loc_us-gaap_InterestRateSwapMember_019e6fc4-5d03-74c3-9294-83fcedd90df9" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_InterestRateSwapInstrument1Member_019e6fc4-5d03-7836-baf0-be88aa9e6b38" xlink:href="smg-20260627.xsd#smg_InterestRateSwapInstrument1Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InterestRateSwapMember_019e6fc4-5d03-74c3-9294-83fcedd90df9" xlink:to="loc_smg_InterestRateSwapInstrument1Member_019e6fc4-5d03-7836-baf0-be88aa9e6b38" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_InterestRateSwapInstrument2Member_019e6fc4-5d03-717f-83fc-6cef6dec3c02" xlink:href="smg-20260627.xsd#smg_InterestRateSwapInstrument2Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InterestRateSwapMember_019e6fc4-5d03-74c3-9294-83fcedd90df9" xlink:to="loc_smg_InterestRateSwapInstrument2Member_019e6fc4-5d03-717f-83fc-6cef6dec3c02" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_InterestRateSwapInstrument3Member_019e6fc4-5d03-7e28-9c8c-f0c5d4b06e04" xlink:href="smg-20260627.xsd#smg_InterestRateSwapInstrument3Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InterestRateSwapMember_019e6fc4-5d03-74c3-9294-83fcedd90df9" xlink:to="loc_smg_InterestRateSwapInstrument3Member_019e6fc4-5d03-7e28-9c8c-f0c5d4b06e04" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_InterestRateSwapInstrument4Member_019e6fc4-5d03-7534-8ac9-1c390c3d0daa" xlink:href="smg-20260627.xsd#smg_InterestRateSwapInstrument4Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InterestRateSwapMember_019e6fc4-5d03-74c3-9294-83fcedd90df9" xlink:to="loc_smg_InterestRateSwapInstrument4Member_019e6fc4-5d03-7534-8ac9-1c390c3d0daa" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_InterestRateSwapInstrument5Member_019e6fc4-5d03-716d-ac72-b4e57122a12b" xlink:href="smg-20260627.xsd#smg_InterestRateSwapInstrument5Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_InterestRateSwapMember_019e6fc4-5d03-74c3-9294-83fcedd90df9" xlink:to="loc_smg_InterestRateSwapInstrument5Member_019e6fc4-5d03-716d-ac72-b4e57122a12b" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeNotionalAmount_019e6fc4-5d03-7612-a959-7e940e508c09" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeNotionalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_019e6fc4-5d03-7c01-9e81-1e8754b04c1c" xlink:to="loc_us-gaap_DerivativeNotionalAmount_019e6fc4-5d03-7612-a959-7e940e508c09" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeFixedInterestRate_019e6fc4-5d03-79cf-a092-82114032b902" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeFixedInterestRate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_019e6fc4-5d03-7c01-9e81-1e8754b04c1c" xlink:to="loc_us-gaap_DerivativeFixedInterestRate_019e6fc4-5d03-79cf-a092-82114032b902" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.scotts.com/role/EQUITYSummaryoftheChangesinEquityDetails" xlink:type="simple" xlink:href="smg-20260627.xsd#EQUITYSummaryoftheChangesinEquityDetails"/>
  <link:definitionLink xlink:role="http://www.scotts.com/role/EQUITYSummaryoftheChangesinEquityDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_019e6fc4-5d03-7dcd-9047-8948bb31f92c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfEquityMethodInvestmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_019e6fc4-5d03-7d2f-8646-b83d2baac870" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfEquityMethodInvestmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_019e6fc4-5d03-7dcd-9047-8948bb31f92c" xlink:to="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_019e6fc4-5d03-7d2f-8646-b83d2baac870" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_019e6fc4-5d03-742f-80a5-852e54ddf25e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_019e6fc4-5d03-7d2f-8646-b83d2baac870" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_019e6fc4-5d03-742f-80a5-852e54ddf25e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_019e6fc4-5d03-742f-80a5-852e54ddf25e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_019e6fc4-5d03-742f-80a5-852e54ddf25e" xlink:to="loc_us-gaap_EquityComponentDomain_019e6fc4-5d03-742f-80a5-852e54ddf25e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_019e6fc4-5d03-7577-8234-e610ccce34c3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_019e6fc4-5d03-742f-80a5-852e54ddf25e" xlink:to="loc_us-gaap_EquityComponentDomain_019e6fc4-5d03-7577-8234-e610ccce34c3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember_019e6fc4-5d03-7375-95d8-428d01b7b982" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019e6fc4-5d03-7577-8234-e610ccce34c3" xlink:to="loc_us-gaap_CommonStockIncludingAdditionalPaidInCapitalMember_019e6fc4-5d03-7375-95d8-428d01b7b982" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsMember_019e6fc4-5d03-710d-a2f5-95392dc91c31" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RetainedEarningsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019e6fc4-5d03-7577-8234-e610ccce34c3" xlink:to="loc_us-gaap_RetainedEarningsMember_019e6fc4-5d03-710d-a2f5-95392dc91c31" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockCommonMember_019e6fc4-5d03-7f22-b2a0-40acff1df191" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TreasuryStockCommonMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019e6fc4-5d03-7577-8234-e610ccce34c3" xlink:to="loc_us-gaap_TreasuryStockCommonMember_019e6fc4-5d03-7f22-b2a0-40acff1df191" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_019e6fc4-5d03-7841-b1db-cf7c3befcc71" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019e6fc4-5d03-7577-8234-e610ccce34c3" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_019e6fc4-5d03-7841-b1db-cf7c3befcc71" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockDividendsPerShareDeclared_019e6fc4-5d03-76b9-a6b1-7e0f4c2c2d36" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockDividendsPerShareDeclared"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_019e6fc4-5d03-7dcd-9047-8948bb31f92c" xlink:to="loc_us-gaap_CommonStockDividendsPerShareDeclared_019e6fc4-5d03-76b9-a6b1-7e0f4c2c2d36" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e6fc4-5d03-73ee-a061-d6a7aefcd6b5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInStockholdersEquityRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_019e6fc4-5d03-7dcd-9047-8948bb31f92c" xlink:to="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e6fc4-5d03-73ee-a061-d6a7aefcd6b5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_019e6fc4-5d03-7bed-b91a-fbc98f69e5b9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e6fc4-5d03-73ee-a061-d6a7aefcd6b5" xlink:to="loc_us-gaap_StockholdersEquity_019e6fc4-5d03-7bed-b91a-fbc98f69e5b9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProfitLoss_019e6fc4-5d03-7811-9387-70f4736bc56b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProfitLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e6fc4-5d03-73ee-a061-d6a7aefcd6b5" xlink:to="loc_us-gaap_ProfitLoss_019e6fc4-5d03-7811-9387-70f4736bc56b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_019e6fc4-5d03-7fdc-9bf0-8364bef7792b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e6fc4-5d03-73ee-a061-d6a7aefcd6b5" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_019e6fc4-5d03-7fdc-9bf0-8364bef7792b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_019e6fc4-5d03-7b93-bc9d-9473c691371d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e6fc4-5d03-73ee-a061-d6a7aefcd6b5" xlink:to="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_019e6fc4-5d03-7b93-bc9d-9473c691371d" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Dividends_019e6fc4-5d03-754a-821e-bc156e683a59" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Dividends"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e6fc4-5d03-73ee-a061-d6a7aefcd6b5" xlink:to="loc_us-gaap_Dividends_019e6fc4-5d03-754a-821e-bc156e683a59" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockValueAcquiredCostMethod_019e6fc4-5d03-7189-8472-cb6bb9e6b05e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TreasuryStockValueAcquiredCostMethod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e6fc4-5d03-73ee-a061-d6a7aefcd6b5" xlink:to="loc_us-gaap_TreasuryStockValueAcquiredCostMethod_019e6fc4-5d03-7189-8472-cb6bb9e6b05e" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueTreasuryStockReissued_019e6fc4-5d03-7792-9ed7-bce986a2da0d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodValueTreasuryStockReissued"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_019e6fc4-5d03-73ee-a061-d6a7aefcd6b5" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueTreasuryStockReissued_019e6fc4-5d03-7792-9ed7-bce986a2da0d" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_019e6fc4-5d03-741f-9a51-b30d65655abc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquity"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.scotts.com/role/EQUITYAccumulatedOtherComprehensiveLossDetails" xlink:type="simple" xlink:href="smg-20260627.xsd#EQUITYAccumulatedOtherComprehensiveLossDetails"/>
  <link:definitionLink xlink:role="http://www.scotts.com/role/EQUITYAccumulatedOtherComprehensiveLossDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_019e6fc4-5d03-7d6f-a821-55205c397f95" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_019e6fc4-5d03-72d1-b8fc-d8affe1cde8a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeLossTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_019e6fc4-5d03-7d6f-a821-55205c397f95" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_019e6fc4-5d03-72d1-b8fc-d8affe1cde8a" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_019e6fc4-5d03-7ad8-a40b-22f1b8eaf0a8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossTable_019e6fc4-5d03-72d1-b8fc-d8affe1cde8a" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_019e6fc4-5d03-7ad8-a40b-22f1b8eaf0a8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_019e6fc4-5d03-7ad8-a40b-22f1b8eaf0a8_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_019e6fc4-5d03-7ad8-a40b-22f1b8eaf0a8" xlink:to="loc_us-gaap_EquityComponentDomain_019e6fc4-5d03-7ad8-a40b-22f1b8eaf0a8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_019e6fc4-5d03-7644-850f-7f2a1231ce3a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_019e6fc4-5d03-7ad8-a40b-22f1b8eaf0a8" xlink:to="loc_us-gaap_EquityComponentDomain_019e6fc4-5d03-7644-850f-7f2a1231ce3a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_019e6fc4-5d03-70aa-86cd-a1cf3fe4d6bc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_019e6fc4-5d03-7644-850f-7f2a1231ce3a" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_019e6fc4-5d03-70aa-86cd-a1cf3fe4d6bc" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedTranslationAdjustmentMember_019e6fc4-5d03-7a2f-bf78-72b27338fcf3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedTranslationAdjustmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_019e6fc4-5d03-70aa-86cd-a1cf3fe4d6bc" xlink:to="loc_us-gaap_AccumulatedTranslationAdjustmentMember_019e6fc4-5d03-7a2f-bf78-72b27338fcf3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedGainLossNetCashFlowHedgeParentMember_019e6fc4-5d03-7c37-b085-99e191f92872" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedGainLossNetCashFlowHedgeParentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_019e6fc4-5d03-70aa-86cd-a1cf3fe4d6bc" xlink:to="loc_us-gaap_AccumulatedGainLossNetCashFlowHedgeParentMember_019e6fc4-5d03-7c37-b085-99e191f92872" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember_019e6fc4-5d03-7945-a05c-219e8b9e6b7f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_019e6fc4-5d03-70aa-86cd-a1cf3fe4d6bc" xlink:to="loc_us-gaap_AccumulatedNetUnrealizedInvestmentGainLossMember_019e6fc4-5d03-7945-a05c-219e8b9e6b7f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember_019e6fc4-5d03-74a8-b666-64fd5725933b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_019e6fc4-5d03-70aa-86cd-a1cf3fe4d6bc" xlink:to="loc_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember_019e6fc4-5d03-74a8-b666-64fd5725933b" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_019e6fc4-5d03-7180-9213-352e2be5d66e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AOCIAttributableToParentNetOfTaxRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeLossLineItems_019e6fc4-5d03-7d6f-a821-55205c397f95" xlink:to="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_019e6fc4-5d03-7180-9213-352e2be5d66e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_019e6fc4-5d03-7d19-8620-6d52c67df77d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_019e6fc4-5d03-7180-9213-352e2be5d66e" xlink:to="loc_us-gaap_StockholdersEquity_019e6fc4-5d03-7d19-8620-6d52c67df77d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OciBeforeReclassificationsBeforeTaxAttributableToParent_019e6fc4-5d03-726b-8c52-900b1d8967d4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OciBeforeReclassificationsBeforeTaxAttributableToParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_019e6fc4-5d03-7180-9213-352e2be5d66e" xlink:to="loc_us-gaap_OciBeforeReclassificationsBeforeTaxAttributableToParent_019e6fc4-5d03-726b-8c52-900b1d8967d4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ReclassificationFromAociCurrentPeriodBeforeTaxAttributableToParent_019e6fc4-5d03-768f-ae9e-735910126e9d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ReclassificationFromAociCurrentPeriodBeforeTaxAttributableToParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_019e6fc4-5d03-7180-9213-352e2be5d66e" xlink:to="loc_us-gaap_ReclassificationFromAociCurrentPeriodBeforeTaxAttributableToParent_019e6fc4-5d03-768f-ae9e-735910126e9d" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossTaxPortionAttributableToParent1_019e6fc4-5d03-7a28-b860-0d4c99ce0ea2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossTaxPortionAttributableToParent1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_019e6fc4-5d03-7180-9213-352e2be5d66e" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossTaxPortionAttributableToParent1_019e6fc4-5d03-7a28-b860-0d4c99ce0ea2" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_019e6fc4-5d03-75f6-9869-6537d4814b1a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AOCIAttributableToParentNetOfTaxRollForward_019e6fc4-5d03-7180-9213-352e2be5d66e" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_019e6fc4-5d03-75f6-9869-6537d4814b1a" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquity_019e6fc4-5d03-7b1c-857d-149689b23c43" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquity"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.scotts.com/role/EQUITYNarrativeDetails" xlink:type="simple" xlink:href="smg-20260627.xsd#EQUITYNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.scotts.com/role/EQUITYNarrativeDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_019e6fc4-5d03-7426-8aa3-86757477aed6" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfEquityMethodInvestmentsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_019e6fc4-5d03-7d62-aad8-83bce456fc97" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfEquityMethodInvestmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_019e6fc4-5d03-7426-8aa3-86757477aed6" xlink:to="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_019e6fc4-5d03-7d62-aad8-83bce456fc97" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_019e6fc4-5d03-76af-a519-0269715342ee" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsTable_019e6fc4-5d03-7d62-aad8-83bce456fc97" xlink:to="loc_us-gaap_AwardTypeAxis_019e6fc4-5d03-76af-a519-0269715342ee" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019e6fc4-5d03-76af-a519-0269715342ee_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_019e6fc4-5d03-76af-a519-0269715342ee" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019e6fc4-5d03-76af-a519-0269715342ee_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019e6fc4-5d03-7592-bd6a-3050fdfd4a69" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_019e6fc4-5d03-76af-a519-0269715342ee" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019e6fc4-5d03-7592-bd6a-3050fdfd4a69" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeStockOptionMember_019e6fc4-5d03-7c77-a4e2-2cb068792593" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EmployeeStockOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019e6fc4-5d03-7592-bd6a-3050fdfd4a69" xlink:to="loc_us-gaap_EmployeeStockOptionMember_019e6fc4-5d03-7c77-a4e2-2cb068792593" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember_019e6fc4-5d03-7125-a731-7e88c42ef135" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestrictedStockUnitsRSUMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_019e6fc4-5d03-7592-bd6a-3050fdfd4a69" xlink:to="loc_us-gaap_RestrictedStockUnitsRSUMember_019e6fc4-5d03-7125-a731-7e88c42ef135" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StockRepurchaseProgramAuthorizedAmount1_019e6fc4-5d03-73b4-ae80-07cf47f173bd" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_StockRepurchaseProgramAuthorizedAmount1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_019e6fc4-5d03-7426-8aa3-86757477aed6" xlink:to="loc_srt_StockRepurchaseProgramAuthorizedAmount1_019e6fc4-5d03-73b4-ae80-07cf47f173bd" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized_019e6fc4-5d03-7740-9752-d3ae6a76dc6f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_019e6fc4-5d03-7426-8aa3-86757477aed6" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized_019e6fc4-5d03-7740-9752-d3ae6a76dc6f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_019e6fc4-5d03-7c19-a0ac-5631c75bc3d7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_019e6fc4-5d03-7426-8aa3-86757477aed6" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_019e6fc4-5d03-7c19-a0ac-5631c75bc3d7" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromStockOptionsExercised_019e6fc4-5d03-7398-b531-9843f5f55289" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromStockOptionsExercised"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_019e6fc4-5d03-7426-8aa3-86757477aed6" xlink:to="loc_us-gaap_ProceedsFromStockOptionsExercised_019e6fc4-5d03-7398-b531-9843f5f55289" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredCompensationShareBasedArrangementsLiabilityCurrent_019e6fc4-5d03-77a2-987f-3556a3c3ff80" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredCompensationShareBasedArrangementsLiabilityCurrent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ScheduleOfEquityMethodInvestmentsLineItems_019e6fc4-5d03-7426-8aa3-86757477aed6" xlink:to="loc_us-gaap_DeferredCompensationShareBasedArrangementsLiabilityCurrent_019e6fc4-5d03-77a2-987f-3556a3c3ff80" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.scotts.com/role/EARNINGSPERCOMMONSHARECalculationofEarningsperShareDetails" xlink:type="simple" xlink:href="smg-20260627.xsd#EARNINGSPERCOMMONSHARECalculationofEarningsperShareDetails"/>
  <link:definitionLink xlink:role="http://www.scotts.com/role/EARNINGSPERCOMMONSHARECalculationofEarningsperShareDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_019e6fc4-5d03-7bd9-b6ff-b58b1c0cc770" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_019e6fc4-5d03-7aa6-af42-f7d0bdec5e34" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_019e6fc4-5d03-7bd9-b6ff-b58b1c0cc770" xlink:to="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_019e6fc4-5d03-7aa6-af42-f7d0bdec5e34" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_019e6fc4-5d03-772a-ad21-a2c6835fae87" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_019e6fc4-5d03-7aa6-af42-f7d0bdec5e34" xlink:to="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_019e6fc4-5d03-772a-ad21-a2c6835fae87" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesNameDomain_019e6fc4-5d03-772a-ad21-a2c6835fae87_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AntidilutiveSecuritiesNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_019e6fc4-5d03-772a-ad21-a2c6835fae87" xlink:to="loc_us-gaap_AntidilutiveSecuritiesNameDomain_019e6fc4-5d03-772a-ad21-a2c6835fae87_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesNameDomain_019e6fc4-5d03-7549-85fb-46f285235847" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AntidilutiveSecuritiesNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_019e6fc4-5d03-772a-ad21-a2c6835fae87" xlink:to="loc_us-gaap_AntidilutiveSecuritiesNameDomain_019e6fc4-5d03-7549-85fb-46f285235847" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeStockOptionMember_019e6fc4-5d03-70d3-b536-1bfe5dcdae90" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EmployeeStockOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_019e6fc4-5d03-7549-85fb-46f285235847" xlink:to="loc_us-gaap_EmployeeStockOptionMember_019e6fc4-5d03-70d3-b536-1bfe5dcdae90" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperations_019e6fc4-5d03-760b-8018-8c3b7323b7a2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromContinuingOperations"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_019e6fc4-5d03-7bd9-b6ff-b58b1c0cc770" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperations_019e6fc4-5d03-760b-8018-8c3b7323b7a2" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity_019e6fc4-5d03-7c3f-8320-5d1bb6212aea" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_019e6fc4-5d03-7bd9-b6ff-b58b1c0cc770" xlink:to="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity_019e6fc4-5d03-7c3f-8320-5d1bb6212aea" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NetIncomeLoss_019e6fc4-5d03-7f24-9de1-3ea26e81a905" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_019e6fc4-5d03-7bd9-b6ff-b58b1c0cc770" xlink:to="loc_us-gaap_NetIncomeLoss_019e6fc4-5d03-7f24-9de1-3ea26e81a905" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareBasicAbstract_019e6fc4-5d03-7936-90a9-639734d25a91" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EarningsPerShareBasicAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_019e6fc4-5d03-7bd9-b6ff-b58b1c0cc770" xlink:to="loc_us-gaap_EarningsPerShareBasicAbstract_019e6fc4-5d03-7936-90a9-639734d25a91" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsPerBasicShare_019e6fc4-5d03-78dc-b41c-34ac76cab044" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromContinuingOperationsPerBasicShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EarningsPerShareBasicAbstract_019e6fc4-5d03-7936-90a9-639734d25a91" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsPerBasicShare_019e6fc4-5d03-78dc-b41c-34ac76cab044" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare_019e6fc4-5d03-71e6-9cce-1ceaefd2ca64" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EarningsPerShareBasicAbstract_019e6fc4-5d03-7936-90a9-639734d25a91" xlink:to="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxPerBasicShare_019e6fc4-5d03-71e6-9cce-1ceaefd2ca64" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareBasic_019e6fc4-5d03-7036-a076-56ff169760f5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EarningsPerShareBasic"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EarningsPerShareBasicAbstract_019e6fc4-5d03-7936-90a9-639734d25a91" xlink:to="loc_us-gaap_EarningsPerShareBasic_019e6fc4-5d03-7036-a076-56ff169760f5" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_019e6fc4-5d03-72c8-a515-449396672f09" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingBasic"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_019e6fc4-5d03-7bd9-b6ff-b58b1c0cc770" xlink:to="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_019e6fc4-5d03-72c8-a515-449396672f09" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareDilutedAbstract_019e6fc4-5d03-7557-b65e-0c2623b1df7b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EarningsPerShareDilutedAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_019e6fc4-5d03-7bd9-b6ff-b58b1c0cc770" xlink:to="loc_us-gaap_EarningsPerShareDilutedAbstract_019e6fc4-5d03-7557-b65e-0c2623b1df7b" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare_019e6fc4-5d03-7dd8-baaa-cc1b936cab50" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EarningsPerShareDilutedAbstract_019e6fc4-5d03-7557-b65e-0c2623b1df7b" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsPerDilutedShare_019e6fc4-5d03-7dd8-baaa-cc1b936cab50" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare_019e6fc4-5d03-780d-929f-9291e7b32f52" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EarningsPerShareDilutedAbstract_019e6fc4-5d03-7557-b65e-0c2623b1df7b" xlink:to="loc_us-gaap_IncomeLossFromDiscontinuedOperationsNetOfTaxPerDilutedShare_019e6fc4-5d03-780d-929f-9291e7b32f52" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EarningsPerShareDiluted_019e6fc4-5d03-7382-aef4-809c7208931f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EarningsPerShareDiluted"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EarningsPerShareDilutedAbstract_019e6fc4-5d03-7557-b65e-0c2623b1df7b" xlink:to="loc_us-gaap_EarningsPerShareDiluted_019e6fc4-5d03-7382-aef4-809c7208931f" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_019e6fc4-5d03-77df-bc66-df0afce82d33" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingBasic"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustment_019e6fc4-5d03-7b20-b0c1-3c4f77356e2e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_019e6fc4-5d03-7bd9-b6ff-b58b1c0cc770" xlink:to="loc_us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustment_019e6fc4-5d03-7b20-b0c1-3c4f77356e2e" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_019e6fc4-5d03-7839-a873-bb8597bad655" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_019e6fc4-5d03-7bd9-b6ff-b58b1c0cc770" xlink:to="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_019e6fc4-5d03-7839-a873-bb8597bad655" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_019e6fc4-5d03-7aba-a706-ae9a40016ee2" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_019e6fc4-5d03-7bd9-b6ff-b58b1c0cc770" xlink:to="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_019e6fc4-5d03-7aba-a706-ae9a40016ee2" xlink:type="arc" order="9"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.scotts.com/role/DERIVATIVEINSTRUMENTSANDHEDGINGACTIVITIESAdditionalInformationDetails" xlink:type="simple" xlink:href="smg-20260627.xsd#DERIVATIVEINSTRUMENTSANDHEDGINGACTIVITIESAdditionalInformationDetails"/>
  <link:definitionLink xlink:role="http://www.scotts.com/role/DERIVATIVEINSTRUMENTSANDHEDGINGACTIVITIESAdditionalInformationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLineItems_019e6fc4-5d03-7814-870c-bdabdaa94aa3" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeTable_019e6fc4-5d03-7c55-9654-e3ff5bb4c861" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeLineItems_019e6fc4-5d03-7814-870c-bdabdaa94aa3" xlink:to="loc_us-gaap_DerivativeTable_019e6fc4-5d03-7c55-9654-e3ff5bb4c861" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6fc4-5d03-77ac-85bc-9c8bcab74ad0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_019e6fc4-5d03-7c55-9654-e3ff5bb4c861" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6fc4-5d03-77ac-85bc-9c8bcab74ad0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019e6fc4-5d03-77ac-85bc-9c8bcab74ad0_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6fc4-5d03-77ac-85bc-9c8bcab74ad0" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019e6fc4-5d03-77ac-85bc-9c8bcab74ad0_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019e6fc4-5d03-7fb3-a1d3-a352d1076457" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6fc4-5d03-77ac-85bc-9c8bcab74ad0" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019e6fc4-5d03-7fb3-a1d3-a352d1076457" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignExchangeForwardMember_019e6fc4-5d03-739f-92d9-fcc8975c1725" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignExchangeForwardMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6fc4-5d03-7fb3-a1d3-a352d1076457" xlink:to="loc_us-gaap_ForeignExchangeForwardMember_019e6fc4-5d03-739f-92d9-fcc8975c1725" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestRateSwapMember_019e6fc4-5d03-7e7f-b177-f99c4b26f250" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestRateSwapMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6fc4-5d03-7fb3-a1d3-a352d1076457" xlink:to="loc_us-gaap_InterestRateSwapMember_019e6fc4-5d03-7e7f-b177-f99c4b26f250" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationAxis_019e6fc4-5d03-7992-bce1-e170ec356b80" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgingDesignationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_019e6fc4-5d03-7c55-9654-e3ff5bb4c861" xlink:to="loc_us-gaap_HedgingDesignationAxis_019e6fc4-5d03-7992-bce1-e170ec356b80" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationDomain_019e6fc4-5d03-7992-bce1-e170ec356b80_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgingDesignationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_HedgingDesignationAxis_019e6fc4-5d03-7992-bce1-e170ec356b80" xlink:to="loc_us-gaap_HedgingDesignationDomain_019e6fc4-5d03-7992-bce1-e170ec356b80_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_HedgingDesignationDomain_019e6fc4-5d03-7ff6-b905-6491162f6e31" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgingDesignationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_HedgingDesignationAxis_019e6fc4-5d03-7992-bce1-e170ec356b80" xlink:to="loc_us-gaap_HedgingDesignationDomain_019e6fc4-5d03-7ff6-b905-6491162f6e31" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NondesignatedMember_019e6fc4-5d03-70ca-9935-b67310ce288c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NondesignatedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingDesignationDomain_019e6fc4-5d03-7ff6-b905-6491162f6e31" xlink:to="loc_us-gaap_NondesignatedMember_019e6fc4-5d03-70ca-9935-b67310ce288c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DesignatedAsHedgingInstrumentMember_019e6fc4-5d03-7a8a-9788-d65248c8d350" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DesignatedAsHedgingInstrumentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_HedgingDesignationDomain_019e6fc4-5d03-7ff6-b905-6491162f6e31" xlink:to="loc_us-gaap_DesignatedAsHedgingInstrumentMember_019e6fc4-5d03-7a8a-9788-d65248c8d350" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeNotionalAmount_019e6fc4-5d03-7a8a-8b87-a356a12f47f9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeNotionalAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_019e6fc4-5d03-7814-870c-bdabdaa94aa3" xlink:to="loc_us-gaap_DerivativeNotionalAmount_019e6fc4-5d03-7a8a-8b87-a356a12f47f9" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.scotts.com/role/DERIVATIVEINSTRUMENTSANDHEDGINGACTIVITIESOutstandingCommodityContractsDetails" xlink:type="simple" xlink:href="smg-20260627.xsd#DERIVATIVEINSTRUMENTSANDHEDGINGACTIVITIESOutstandingCommodityContractsDetails"/>
  <link:definitionLink xlink:role="http://www.scotts.com/role/DERIVATIVEINSTRUMENTSANDHEDGINGACTIVITIESOutstandingCommodityContractsDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeLineItems_019e6fc4-5d03-7f5b-9f18-3abcc50d2480" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeTable_019e6fc4-5d03-7e35-846c-79c8ab166d9f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DerivativeLineItems_019e6fc4-5d03-7f5b-9f18-3abcc50d2480" xlink:to="loc_us-gaap_DerivativeTable_019e6fc4-5d03-7e35-846c-79c8ab166d9f" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6fc4-5d03-7872-9284-5e8253e4506a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentRiskAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DerivativeTable_019e6fc4-5d03-7e35-846c-79c8ab166d9f" xlink:to="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6fc4-5d03-7872-9284-5e8253e4506a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019e6fc4-5d03-7872-9284-5e8253e4506a_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6fc4-5d03-7872-9284-5e8253e4506a" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019e6fc4-5d03-7872-9284-5e8253e4506a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeContractTypeDomain_019e6fc4-5d03-77ca-8d60-331a834214f4" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis_019e6fc4-5d03-7872-9284-5e8253e4506a" xlink:to="loc_us-gaap_DerivativeContractTypeDomain_019e6fc4-5d03-77ca-8d60-331a834214f4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_UreaMember_019e6fc4-5d03-7052-b4f1-52cb655b1bd0" xlink:href="smg-20260627.xsd#smg_UreaMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6fc4-5d03-77ca-8d60-331a834214f4" xlink:to="loc_smg_UreaMember_019e6fc4-5d03-7052-b4f1-52cb655b1bd0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_DieselFuelMember_019e6fc4-5d03-7d84-aae7-be20aa25603a" xlink:href="smg-20260627.xsd#smg_DieselFuelMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6fc4-5d03-77ca-8d60-331a834214f4" xlink:to="loc_smg_DieselFuelMember_019e6fc4-5d03-7d84-aae7-be20aa25603a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_HeatingOilMember_019e6fc4-5d03-781e-8dcc-51cc44aa126d" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_HeatingOilMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeContractTypeDomain_019e6fc4-5d03-77ca-8d60-331a834214f4" xlink:to="loc_srt_HeatingOilMember_019e6fc4-5d03-781e-8dcc-51cc44aa126d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeNonmonetaryNotionalAmountMass_019e6fc4-5d03-7686-a810-54cf1099576b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeNonmonetaryNotionalAmountMass"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_019e6fc4-5d03-7f5b-9f18-3abcc50d2480" xlink:to="loc_us-gaap_DerivativeNonmonetaryNotionalAmountMass_019e6fc4-5d03-7686-a810-54cf1099576b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DerivativeNonmonetaryNotionalAmountVolume_019e6fc4-5d03-7b4f-ad7a-42eae6cfa110" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeNonmonetaryNotionalAmountVolume"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DerivativeLineItems_019e6fc4-5d03-7f5b-9f18-3abcc50d2480" xlink:to="loc_us-gaap_DerivativeNonmonetaryNotionalAmountVolume_019e6fc4-5d03-7b4f-ad7a-42eae6cfa110" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.scotts.com/role/FAIRVALUEMEASUREMENTSSummaryofFairValueofAssetsandLiabilitiesDetails" xlink:type="simple" xlink:href="smg-20260627.xsd#FAIRVALUEMEASUREMENTSSummaryofFairValueofAssetsandLiabilitiesDetails"/>
  <link:definitionLink xlink:role="http://www.scotts.com/role/FAIRVALUEMEASUREMENTSSummaryofFairValueofAssetsandLiabilitiesDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e6fc4-5d03-7a61-ac61-e4c043e94453" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e6fc4-5d03-7dcd-9b81-8551d8ce397d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e6fc4-5d03-7a61-ac61-e4c043e94453" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e6fc4-5d03-7dcd-9b81-8551d8ce397d" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByMeasurementBasisAxis_019e6fc4-5d03-7b31-9ef4-d2982cc3213e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByMeasurementBasisAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e6fc4-5d03-7dcd-9b81-8551d8ce397d" xlink:to="loc_us-gaap_FairValueByMeasurementBasisAxis_019e6fc4-5d03-7b31-9ef4-d2982cc3213e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_019e6fc4-5d03-7b31-9ef4-d2982cc3213e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PortionAtFairValueFairValueDisclosureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByMeasurementBasisAxis_019e6fc4-5d03-7b31-9ef4-d2982cc3213e" xlink:to="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_019e6fc4-5d03-7b31-9ef4-d2982cc3213e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueDisclosureItemAmountsDomain_019e6fc4-5d03-7cd8-a7c3-250e89ae1a6c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueDisclosureItemAmountsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByMeasurementBasisAxis_019e6fc4-5d03-7b31-9ef4-d2982cc3213e" xlink:to="loc_us-gaap_FairValueDisclosureItemAmountsDomain_019e6fc4-5d03-7cd8-a7c3-250e89ae1a6c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_019e6fc4-5d03-70bf-bce8-6bb968bcc9ca" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PortionAtFairValueFairValueDisclosureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueDisclosureItemAmountsDomain_019e6fc4-5d03-7cd8-a7c3-250e89ae1a6c" xlink:to="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_019e6fc4-5d03-70bf-bce8-6bb968bcc9ca" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CarryingReportedAmountFairValueDisclosureMember_019e6fc4-5d03-7405-a68a-e757452281e8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CarryingReportedAmountFairValueDisclosureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_019e6fc4-5d03-70bf-bce8-6bb968bcc9ca" xlink:to="loc_us-gaap_CarryingReportedAmountFairValueDisclosureMember_019e6fc4-5d03-7405-a68a-e757452281e8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EstimateOfFairValueFairValueDisclosureMember_019e6fc4-5d03-74f1-9515-6181ac996dc5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EstimateOfFairValueFairValueDisclosureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PortionAtFairValueFairValueDisclosureMember_019e6fc4-5d03-70bf-bce8-6bb968bcc9ca" xlink:to="loc_us-gaap_EstimateOfFairValueFairValueDisclosureMember_019e6fc4-5d03-74f1-9515-6181ac996dc5" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e6fc4-5d03-7341-b5bf-2bd207aff1dd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e6fc4-5d03-7dcd-9b81-8551d8ce397d" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e6fc4-5d03-7341-b5bf-2bd207aff1dd" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6fc4-5d03-7341-b5bf-2bd207aff1dd_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e6fc4-5d03-7341-b5bf-2bd207aff1dd" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6fc4-5d03-7341-b5bf-2bd207aff1dd_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6fc4-5d03-72c3-b426-0f056933cc4d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e6fc4-5d03-7341-b5bf-2bd207aff1dd" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6fc4-5d03-72c3-b426-0f056933cc4d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel1Member_019e6fc4-5d03-7e21-aab4-e682f9f5f6fc" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel1Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6fc4-5d03-72c3-b426-0f056933cc4d" xlink:to="loc_us-gaap_FairValueInputsLevel1Member_019e6fc4-5d03-7e21-aab4-e682f9f5f6fc" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel2Member_019e6fc4-5d03-7f0d-9848-e6500a1c8a83" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel2Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6fc4-5d03-72c3-b426-0f056933cc4d" xlink:to="loc_us-gaap_FairValueInputsLevel2Member_019e6fc4-5d03-7f0d-9848-e6500a1c8a83" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel3Member_019e6fc4-5d03-7f32-a518-f217ca2c0121" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel3Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6fc4-5d03-72c3-b426-0f056933cc4d" xlink:to="loc_us-gaap_FairValueInputsLevel3Member_019e6fc4-5d03-7f32-a518-f217ca2c0121" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019e6fc4-5d03-704d-86a7-da1a70389c97" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByMeasurementFrequencyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e6fc4-5d03-7dcd-9b81-8551d8ce397d" xlink:to="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019e6fc4-5d03-704d-86a7-da1a70389c97" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6fc4-5d03-704d-86a7-da1a70389c97_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019e6fc4-5d03-704d-86a7-da1a70389c97" xlink:to="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6fc4-5d03-704d-86a7-da1a70389c97_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6fc4-5d03-75eb-a76d-32d09dba28da" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019e6fc4-5d03-704d-86a7-da1a70389c97" xlink:to="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6fc4-5d03-75eb-a76d-32d09dba28da" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsRecurringMember_019e6fc4-5d03-73e7-be7c-345e3e2c4f02" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsRecurringMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6fc4-5d03-75eb-a76d-32d09dba28da" xlink:to="loc_us-gaap_FairValueMeasurementsRecurringMember_019e6fc4-5d03-73e7-be7c-345e3e2c4f02" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByAssetClassAxis_019e6fc4-5d03-7849-a5a0-0bb067b2e6dd" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByAssetClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e6fc4-5d03-7dcd-9b81-8551d8ce397d" xlink:to="loc_us-gaap_FairValueByAssetClassAxis_019e6fc4-5d03-7849-a5a0-0bb067b2e6dd" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_019e6fc4-5d03-7849-a5a0-0bb067b2e6dd_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByAssetClassAxis_019e6fc4-5d03-7849-a5a0-0bb067b2e6dd" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_019e6fc4-5d03-7849-a5a0-0bb067b2e6dd_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_019e6fc4-5d03-71cf-a71f-07c08a6d0dfe" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByAssetClassAxis_019e6fc4-5d03-7849-a5a0-0bb067b2e6dd" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_019e6fc4-5d03-71cf-a71f-07c08a6d0dfe" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SecuritiesInvestmentMember_019e6fc4-5d03-7b8e-8efb-b1040b0058c1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SecuritiesInvestmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_019e6fc4-5d03-71cf-a71f-07c08a6d0dfe" xlink:to="loc_us-gaap_SecuritiesInvestmentMember_019e6fc4-5d03-7b8e-8efb-b1040b0058c1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockMember_019fc99f-6f4f-78c4-b6ed-e9f7c560f095" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_019e6fc4-5d03-71cf-a71f-07c08a6d0dfe" xlink:to="loc_us-gaap_CommonStockMember_019fc99f-6f4f-78c4-b6ed-e9f7c560f095" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_WarrantMember_019fc99f-8dc5-70bf-bfba-dad2b821eeed" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_WarrantMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_019e6fc4-5d03-71cf-a71f-07c08a6d0dfe" xlink:to="loc_us-gaap_WarrantMember_019fc99f-8dc5-70bf-bfba-dad2b821eeed" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConvertibleDebtSecuritiesMember_019e6fc4-5d03-7750-b5f3-aa223d880a13" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConvertibleDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain_019e6fc4-5d03-71cf-a71f-07c08a6d0dfe" xlink:to="loc_us-gaap_ConvertibleDebtSecuritiesMember_019e6fc4-5d03-7750-b5f3-aa223d880a13" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_019e6fc4-5d03-76eb-8ad3-5c25e8ce1d1e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e6fc4-5d03-7dcd-9b81-8551d8ce397d" xlink:to="loc_us-gaap_LongtermDebtTypeAxis_019e6fc4-5d03-76eb-8ad3-5c25e8ce1d1e" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019e6fc4-5d03-76eb-8ad3-5c25e8ce1d1e_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_019e6fc4-5d03-76eb-8ad3-5c25e8ce1d1e" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019e6fc4-5d03-76eb-8ad3-5c25e8ce1d1e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_019e6fc4-5d03-7638-b13c-018d29c22a3e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_019e6fc4-5d03-76eb-8ad3-5c25e8ce1d1e" xlink:to="loc_us-gaap_LongtermDebtTypeDomain_019e6fc4-5d03-7638-b13c-018d29c22a3e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditMember_019e6fc4-5d03-7c0a-aa42-812286953148" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_019e6fc4-5d03-7638-b13c-018d29c22a3e" xlink:to="loc_us-gaap_LineOfCreditMember_019e6fc4-5d03-7c0a-aa42-812286953148" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeniorNotesMember_019e6fc4-5d03-7a87-8b4e-ba438a04f48b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SeniorNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_019e6fc4-5d03-7638-b13c-018d29c22a3e" xlink:to="loc_us-gaap_SeniorNotesMember_019e6fc4-5d03-7a87-8b4e-ba438a04f48b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_OtherLongtermDebtMember_019e6fc4-5d03-7041-af7b-f2232fffa29a" xlink:href="smg-20260627.xsd#smg_OtherLongtermDebtMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_019e6fc4-5d03-7638-b13c-018d29c22a3e" xlink:to="loc_smg_OtherLongtermDebtMember_019e6fc4-5d03-7041-af7b-f2232fffa29a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityAxis_019e6fc4-5d03-719d-b832-7f8af784c18f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e6fc4-5d03-7dcd-9b81-8551d8ce397d" xlink:to="loc_us-gaap_CreditFacilityAxis_019e6fc4-5d03-719d-b832-7f8af784c18f" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_019e6fc4-5d03-719d-b832-7f8af784c18f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_CreditFacilityAxis_019e6fc4-5d03-719d-b832-7f8af784c18f" xlink:to="loc_us-gaap_CreditFacilityDomain_019e6fc4-5d03-719d-b832-7f8af784c18f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CreditFacilityDomain_019e6fc4-5d03-758c-8bd4-1fc4b84b8a24" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_CreditFacilityAxis_019e6fc4-5d03-719d-b832-7f8af784c18f" xlink:to="loc_us-gaap_CreditFacilityDomain_019e6fc4-5d03-758c-8bd4-1fc4b84b8a24" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevolvingCreditFacilityMember_019e6fc4-5d03-7ab8-a0a2-24cb38995e15" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevolvingCreditFacilityMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_019e6fc4-5d03-758c-8bd4-1fc4b84b8a24" xlink:to="loc_us-gaap_RevolvingCreditFacilityMember_019e6fc4-5d03-7ab8-a0a2-24cb38995e15" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_TermLoanMember_019e6fc4-5d03-7759-ad69-228b09ddbdb4" xlink:href="smg-20260627.xsd#smg_TermLoanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_CreditFacilityDomain_019e6fc4-5d03-758c-8bd4-1fc4b84b8a24" xlink:to="loc_smg_TermLoanMember_019e6fc4-5d03-7759-ad69-228b09ddbdb4" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentAxis_019e6fc4-5d03-72c1-839b-a73eb94dedf5" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e6fc4-5d03-7dcd-9b81-8551d8ce397d" xlink:to="loc_us-gaap_DebtInstrumentAxis_019e6fc4-5d03-72c1-839b-a73eb94dedf5" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019e6fc4-5d03-72c1-839b-a73eb94dedf5_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DebtInstrumentAxis_019e6fc4-5d03-72c1-839b-a73eb94dedf5" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019e6fc4-5d03-72c1-839b-a73eb94dedf5_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_019e6fc4-5d03-7fe1-9193-99ebf3d7df3a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DebtInstrumentAxis_019e6fc4-5d03-72c1-839b-a73eb94dedf5" xlink:to="loc_us-gaap_DebtInstrumentNameDomain_019e6fc4-5d03-7fe1-9193-99ebf3d7df3a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_A4000SeniorNotesMember_019e6fc4-5d03-7122-b8ad-ea96205eb45c" xlink:href="smg-20260627.xsd#smg_A4000SeniorNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019e6fc4-5d03-7fe1-9193-99ebf3d7df3a" xlink:to="loc_smg_A4000SeniorNotesMember_019e6fc4-5d03-7122-b8ad-ea96205eb45c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_A4375SeniorNotesMember_019e6fc4-5d03-7df6-85a2-00cc24d49adc" xlink:href="smg-20260627.xsd#smg_A4375SeniorNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019e6fc4-5d03-7fe1-9193-99ebf3d7df3a" xlink:to="loc_smg_A4375SeniorNotesMember_019e6fc4-5d03-7df6-85a2-00cc24d49adc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_A4500SeniorNotesMember_019e6fc4-5d03-7af3-90e4-4cb1e5333097" xlink:href="smg-20260627.xsd#smg_A4500SeniorNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019e6fc4-5d03-7fe1-9193-99ebf3d7df3a" xlink:to="loc_smg_A4500SeniorNotesMember_019e6fc4-5d03-7af3-90e4-4cb1e5333097" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_A5250SeniorNotesMember_019e6fc4-5d03-7558-bbed-8e55b7badb17" xlink:href="smg-20260627.xsd#smg_A5250SeniorNotesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_019e6fc4-5d03-7fe1-9193-99ebf3d7df3a" xlink:to="loc_smg_A5250SeniorNotesMember_019e6fc4-5d03-7558-bbed-8e55b7badb17" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AssetsFairValueDisclosureAbstract_019e6fc4-5d03-7d5e-b941-71cc9355245e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsFairValueDisclosureAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e6fc4-5d03-7a61-ac61-e4c043e94453" xlink:to="loc_us-gaap_AssetsFairValueDisclosureAbstract_019e6fc4-5d03-7d5e-b941-71cc9355245e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CashAndCashEquivalentsFairValueDisclosure_019e6fc4-5d03-70af-b972-a0db38df17f0" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashAndCashEquivalentsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_019e6fc4-5d03-7d5e-b941-71cc9355245e" xlink:to="loc_us-gaap_CashAndCashEquivalentsFairValueDisclosure_019e6fc4-5d03-70af-b972-a0db38df17f0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherAssetsFairValueDisclosure_019e6fc4-5d03-753f-b599-084930e24051" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherAssetsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AssetsFairValueDisclosureAbstract_019e6fc4-5d03-7d5e-b941-71cc9355245e" xlink:to="loc_us-gaap_OtherAssetsFairValueDisclosure_019e6fc4-5d03-753f-b599-084930e24051" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_019e6fc4-5d03-70d0-9300-d249a86630fa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesFairValueDisclosureAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e6fc4-5d03-7a61-ac61-e4c043e94453" xlink:to="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_019e6fc4-5d03-70d0-9300-d249a86630fa" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LongTermDebtFairValue_019e6fc4-5d03-76bc-9e9c-fd0beca15b34" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_019e6fc4-5d03-70d0-9300-d249a86630fa" xlink:to="loc_us-gaap_LongTermDebtFairValue_019e6fc4-5d03-76bc-9e9c-fd0beca15b34" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_019e6fc4-5d03-7145-95c5-5f1a6f7efafa" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosureAbstract_019e6fc4-5d03-70d0-9300-d249a86630fa" xlink:to="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_019e6fc4-5d03-7145-95c5-5f1a6f7efafa" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.scotts.com/role/FAIRVALUEMEASUREMENTSRollforwardDetails" xlink:type="simple" xlink:href="smg-20260627.xsd#FAIRVALUEMEASUREMENTSRollforwardDetails"/>
  <link:definitionLink xlink:role="http://www.scotts.com/role/FAIRVALUEMEASUREMENTSRollforwardDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e6fc4-5d03-78e0-b7bc-1a061037e725" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e6fc4-5d03-774c-a762-0b4295e87664" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e6fc4-5d03-78e0-b7bc-1a061037e725" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e6fc4-5d03-774c-a762-0b4295e87664" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e6fc4-5d03-784c-827c-52a33ddb2293" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e6fc4-5d03-774c-a762-0b4295e87664" xlink:to="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e6fc4-5d03-784c-827c-52a33ddb2293" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6fc4-5d03-784c-827c-52a33ddb2293_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e6fc4-5d03-784c-827c-52a33ddb2293" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6fc4-5d03-784c-827c-52a33ddb2293_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6fc4-5d03-7e9c-b899-04d20f3ef551" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis_019e6fc4-5d03-784c-827c-52a33ddb2293" xlink:to="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6fc4-5d03-7e9c-b899-04d20f3ef551" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueInputsLevel3Member_019e6fc4-5d03-7072-ba15-454b2e19882e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel3Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain_019e6fc4-5d03-7e9c-b899-04d20f3ef551" xlink:to="loc_us-gaap_FairValueInputsLevel3Member_019e6fc4-5d03-7072-ba15-454b2e19882e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019e6fc4-5d03-720c-8a66-31108b32ed02" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByMeasurementFrequencyAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019e6fc4-5d03-774c-a762-0b4295e87664" xlink:to="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019e6fc4-5d03-720c-8a66-31108b32ed02" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6fc4-5d03-720c-8a66-31108b32ed02_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019e6fc4-5d03-720c-8a66-31108b32ed02" xlink:to="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6fc4-5d03-720c-8a66-31108b32ed02_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6fc4-5d03-7ae9-afe0-85a2943e01e8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementFrequencyDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FairValueByMeasurementFrequencyAxis_019e6fc4-5d03-720c-8a66-31108b32ed02" xlink:to="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6fc4-5d03-7ae9-afe0-85a2943e01e8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementsRecurringMember_019e6fc4-5d03-7d18-9605-1ada00b19811" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsRecurringMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueMeasurementFrequencyDomain_019e6fc4-5d03-7ae9-afe0-85a2943e01e8" xlink:to="loc_us-gaap_FairValueMeasurementsRecurringMember_019e6fc4-5d03-7d18-9605-1ada00b19811" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019e6fc4-5d03-73ae-bf67-98289261e946" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019e6fc4-5d03-78e0-b7bc-1a061037e725" xlink:to="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019e6fc4-5d03-73ae-bf67-98289261e946" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue_019e6fc4-5d03-7630-8ca9-fae6504cae35" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019e6fc4-5d03-73ae-bf67-98289261e946" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue_019e6fc4-5d03-7630-8ca9-fae6504cae35" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases_019e6fc4-5d03-7bde-bbb6-bbde6e04bdf9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019e6fc4-5d03-73ae-bf67-98289261e946" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases_019e6fc4-5d03-7bde-bbb6-bbde6e04bdf9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisSecuritiesReceivedForSaleOfBusiness_019fc9a2-0e8f-71a4-8181-e5b9bf9f7ae8" xlink:href="smg-20260627.xsd#smg_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisSecuritiesReceivedForSaleOfBusiness"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019e6fc4-5d03-73ae-bf67-98289261e946" xlink:to="loc_smg_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisSecuritiesReceivedForSaleOfBusiness_019fc9a2-0e8f-71a4-8181-e5b9bf9f7ae8" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1_019e6fc4-5d03-78fa-93c4-0fbc8c0d7cfe" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019e6fc4-5d03-73ae-bf67-98289261e946" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1_019e6fc4-5d03-78fa-93c4-0fbc8c0d7cfe" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss_019e6fc4-5d03-7a30-b250-3b4618a5d89f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019e6fc4-5d03-73ae-bf67-98289261e946" xlink:to="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss_019e6fc4-5d03-7a30-b250-3b4618a5d89f" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetExchange_019e6fc4-5d03-70dd-825b-d4a304892b5d" xlink:href="smg-20260627.xsd#smg_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetExchange"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward_019e6fc4-5d03-73ae-bf67-98289261e946" xlink:to="loc_smg_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetExchange_019e6fc4-5d03-70dd-825b-d4a304892b5d" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue_019e6fc4-5d03-7dd6-8424-af2a393ba5cf" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.scotts.com/role/FAIRVALUEMEASUREMENTSAdditionalInformationDetails" xlink:type="simple" xlink:href="smg-20260627.xsd#FAIRVALUEMEASUREMENTSAdditionalInformationDetails"/>
  <link:definitionLink xlink:role="http://www.scotts.com/role/FAIRVALUEMEASUREMENTSAdditionalInformationDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019fb514-11d0-72c1-933b-34a88abeda31" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019fb514-11d0-7862-8438-746b579c5b5f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019fb514-11d0-72c1-933b-34a88abeda31" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019fb514-11d0-7862-8438-746b579c5b5f" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_019fb514-11d0-7540-ba1c-04ae687c6f79" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019fb514-11d0-7862-8438-746b579c5b5f" xlink:to="loc_us-gaap_FinancialInstrumentAxis_019fb514-11d0-7540-ba1c-04ae687c6f79" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019fb514-11d0-7540-ba1c-04ae687c6f79_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019fb514-11d0-7540-ba1c-04ae687c6f79" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019fb514-11d0-7540-ba1c-04ae687c6f79_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019fb514-11d0-71bb-9761-d69248816b1f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019fb514-11d0-7540-ba1c-04ae687c6f79" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019fb514-11d0-71bb-9761-d69248816b1f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConvertibleDebtSecuritiesMember_019fb514-11d0-7568-80d8-4e749cecce8a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConvertibleDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019fb514-11d0-71bb-9761-d69248816b1f" xlink:to="loc_us-gaap_ConvertibleDebtSecuritiesMember_019fb514-11d0-7568-80d8-4e749cecce8a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_019fb514-11d0-7aaf-af28-578e1edff23c" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019fb514-11d0-7862-8438-746b579c5b5f" xlink:to="loc_srt_RangeAxis_019fb514-11d0-7aaf-af28-578e1edff23c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019fb514-11d0-7aaf-af28-578e1edff23c_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_019fb514-11d0-7aaf-af28-578e1edff23c" xlink:to="loc_srt_RangeMember_019fb514-11d0-7aaf-af28-578e1edff23c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019fb514-11d0-7343-b68d-fc7892812368" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_019fb514-11d0-7aaf-af28-578e1edff23c" xlink:to="loc_srt_RangeMember_019fb514-11d0-7343-b68d-fc7892812368" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_019fb514-11d0-79ed-89f0-38e1035dd2d0" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019fb514-11d0-7343-b68d-fc7892812368" xlink:to="loc_srt_MaximumMember_019fb514-11d0-79ed-89f0-38e1035dd2d0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_OwnershipAxis_019fcdc2-d477-7414-878b-6cc38c7f54ed" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_OwnershipAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019fb514-11d0-7862-8438-746b579c5b5f" xlink:to="loc_srt_OwnershipAxis_019fcdc2-d477-7414-878b-6cc38c7f54ed" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_OwnershipDomain_019fcdc2-d477-7414-878b-6cc38c7f54ed_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_OwnershipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_OwnershipAxis_019fcdc2-d477-7414-878b-6cc38c7f54ed" xlink:to="loc_srt_OwnershipDomain_019fcdc2-d477-7414-878b-6cc38c7f54ed_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_OwnershipDomain_019fcdc2-d477-791f-88b9-f6fea791a272" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_OwnershipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_OwnershipAxis_019fcdc2-d477-7414-878b-6cc38c7f54ed" xlink:to="loc_srt_OwnershipDomain_019fcdc2-d477-791f-88b9-f6fea791a272" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_VireoMember_019fcdc2-d477-7283-9a39-76415fc57da5" xlink:href="smg-20260627.xsd#smg_VireoMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_OwnershipDomain_019fcdc2-d477-791f-88b9-f6fea791a272" xlink:to="loc_smg_VireoMember_019fcdc2-d477-7283-9a39-76415fc57da5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementOfIncomeLocationBalanceAxis_019fcdc5-6baf-7125-8d57-c1e4a1fe40b1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementOfIncomeLocationBalanceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019fb514-11d0-7862-8438-746b579c5b5f" xlink:to="loc_us-gaap_StatementOfIncomeLocationBalanceAxis_019fcdc5-6baf-7125-8d57-c1e4a1fe40b1" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtCost_019fb514-11d0-7a2c-9c6e-439e3bcd2282" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedAtCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019fb514-11d0-72c1-933b-34a88abeda31" xlink:to="loc_us-gaap_InvestmentOwnedAtCost_019fb514-11d0-7a2c-9c6e-439e3bcd2282" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedGainLoss_019fb514-11d0-70fa-98c8-150eb204e5a7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleUnrealizedGainLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019fb514-11d0-72c1-933b-34a88abeda31" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedGainLoss_019fb514-11d0-70fa-98c8-150eb204e5a7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleAllowanceForCreditLoss_019fb514-11d0-7f0d-8b12-f16d5c3cb9f9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019fb514-11d0-72c1-933b-34a88abeda31" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleAllowanceForCreditLoss_019fb514-11d0-7f0d-8b12-f16d5c3cb9f9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTerm_019fb514-11d0-7c3e-93dc-cf4f5a03fbba" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentTerm"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019fb514-11d0-72c1-933b-34a88abeda31" xlink:to="loc_us-gaap_DebtInstrumentTerm_019fb514-11d0-7c3e-93dc-cf4f5a03fbba" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityNoteStockSplitConversionRatio1_019fcdc2-d477-79f2-852e-f0c144b4db09" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquityNoteStockSplitConversionRatio1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019fb514-11d0-72c1-933b-34a88abeda31" xlink:to="loc_us-gaap_StockholdersEquityNoteStockSplitConversionRatio1_019fcdc2-d477-79f2-852e-f0c144b4db09" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedBalanceShares_019fcdc2-d477-7d77-a9b6-d6c0ae51192c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedBalanceShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019fb514-11d0-72c1-933b-34a88abeda31" xlink:to="loc_us-gaap_InvestmentOwnedBalanceShares_019fcdc2-d477-7d77-a9b6-d6c0ae51192c" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights_019fcdc2-d477-7e9f-b213-6ca56bfae3b1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019fb514-11d0-72c1-933b-34a88abeda31" xlink:to="loc_us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights_019fcdc2-d477-7e9f-b213-6ca56bfae3b1" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_019fcdc2-d477-753c-b417-e2350217857d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019fb514-11d0-72c1-933b-34a88abeda31" xlink:to="loc_us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_019fcdc2-d477-753c-b417-e2350217857d" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtFairValue_019fcdc2-d477-7a49-afaa-4979047df07f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019fb514-11d0-72c1-933b-34a88abeda31" xlink:to="loc_us-gaap_InvestmentOwnedAtFairValue_019fcdc2-d477-7a49-afaa-4979047df07f" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnrealizedGainLossOnInvestments_019fcdc5-6baf-791a-bf69-48cacfa7e015" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_UnrealizedGainLossOnInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019fb514-11d0-72c1-933b-34a88abeda31" xlink:to="loc_us-gaap_UnrealizedGainLossOnInvestments_019fcdc5-6baf-791a-bf69-48cacfa7e015" xlink:type="arc" order="9"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.scotts.com/role/FAIRVALUEMEASUREMENTSAdditionalInformationDetails_1" xlink:type="simple" xlink:href="smg-20260627.xsd#FAIRVALUEMEASUREMENTSAdditionalInformationDetails_1"/>
  <link:definitionLink xlink:role="http://www.scotts.com/role/FAIRVALUEMEASUREMENTSAdditionalInformationDetails_1" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019fb514-11d0-72c1-933b-34a88abeda31" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019fb514-11d0-7862-8438-746b579c5b5f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019fb514-11d0-72c1-933b-34a88abeda31" xlink:to="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019fb514-11d0-7862-8438-746b579c5b5f" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FinancialInstrumentAxis_019fb514-11d0-7540-ba1c-04ae687c6f79" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialInstrumentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019fb514-11d0-7862-8438-746b579c5b5f" xlink:to="loc_us-gaap_FinancialInstrumentAxis_019fb514-11d0-7540-ba1c-04ae687c6f79" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019fb514-11d0-7540-ba1c-04ae687c6f79_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019fb514-11d0-7540-ba1c-04ae687c6f79" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019fb514-11d0-7540-ba1c-04ae687c6f79_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019fb514-11d0-71bb-9761-d69248816b1f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FinancialInstrumentAxis_019fb514-11d0-7540-ba1c-04ae687c6f79" xlink:to="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019fb514-11d0-71bb-9761-d69248816b1f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConvertibleDebtSecuritiesMember_019fb514-11d0-7568-80d8-4e749cecce8a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConvertibleDebtSecuritiesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain_019fb514-11d0-71bb-9761-d69248816b1f" xlink:to="loc_us-gaap_ConvertibleDebtSecuritiesMember_019fb514-11d0-7568-80d8-4e749cecce8a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_019fb514-11d0-7aaf-af28-578e1edff23c" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019fb514-11d0-7862-8438-746b579c5b5f" xlink:to="loc_srt_RangeAxis_019fb514-11d0-7aaf-af28-578e1edff23c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019fb514-11d0-7aaf-af28-578e1edff23c_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_019fb514-11d0-7aaf-af28-578e1edff23c" xlink:to="loc_srt_RangeMember_019fb514-11d0-7aaf-af28-578e1edff23c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_019fb514-11d0-7343-b68d-fc7892812368" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_019fb514-11d0-7aaf-af28-578e1edff23c" xlink:to="loc_srt_RangeMember_019fb514-11d0-7343-b68d-fc7892812368" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_019fb514-11d0-79ed-89f0-38e1035dd2d0" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_019fb514-11d0-7343-b68d-fc7892812368" xlink:to="loc_srt_MaximumMember_019fb514-11d0-79ed-89f0-38e1035dd2d0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_OwnershipAxis_019fcdc2-d477-7414-878b-6cc38c7f54ed" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_OwnershipAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable_019fb514-11d0-7862-8438-746b579c5b5f" xlink:to="loc_srt_OwnershipAxis_019fcdc2-d477-7414-878b-6cc38c7f54ed" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_OwnershipDomain_019fcdc2-d477-7414-878b-6cc38c7f54ed_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_OwnershipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_OwnershipAxis_019fcdc2-d477-7414-878b-6cc38c7f54ed" xlink:to="loc_srt_OwnershipDomain_019fcdc2-d477-7414-878b-6cc38c7f54ed_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_OwnershipDomain_019fcdc2-d477-791f-88b9-f6fea791a272" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_OwnershipDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_OwnershipAxis_019fcdc2-d477-7414-878b-6cc38c7f54ed" xlink:to="loc_srt_OwnershipDomain_019fcdc2-d477-791f-88b9-f6fea791a272" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_VireoMember_019fcdc2-d477-7283-9a39-76415fc57da5" xlink:href="smg-20260627.xsd#smg_VireoMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_OwnershipDomain_019fcdc2-d477-791f-88b9-f6fea791a272" xlink:to="loc_smg_VireoMember_019fcdc2-d477-7283-9a39-76415fc57da5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtCost_019fb514-11d0-7a2c-9c6e-439e3bcd2282" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedAtCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019fb514-11d0-72c1-933b-34a88abeda31" xlink:to="loc_us-gaap_InvestmentOwnedAtCost_019fb514-11d0-7a2c-9c6e-439e3bcd2282" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedGainLoss_019fb514-11d0-70fa-98c8-150eb204e5a7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleUnrealizedGainLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019fb514-11d0-72c1-933b-34a88abeda31" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleUnrealizedGainLoss_019fb514-11d0-70fa-98c8-150eb204e5a7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtSecuritiesAvailableForSaleAllowanceForCreditLoss_019fb514-11d0-7f0d-8b12-f16d5c3cb9f9" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtSecuritiesAvailableForSaleAllowanceForCreditLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019fb514-11d0-72c1-933b-34a88abeda31" xlink:to="loc_us-gaap_DebtSecuritiesAvailableForSaleAllowanceForCreditLoss_019fb514-11d0-7f0d-8b12-f16d5c3cb9f9" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DebtInstrumentTerm_019fb514-11d0-7c3e-93dc-cf4f5a03fbba" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentTerm"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019fb514-11d0-72c1-933b-34a88abeda31" xlink:to="loc_us-gaap_DebtInstrumentTerm_019fb514-11d0-7c3e-93dc-cf4f5a03fbba" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityNoteStockSplitConversionRatio1_019fcdc2-d477-79f2-852e-f0c144b4db09" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquityNoteStockSplitConversionRatio1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019fb514-11d0-72c1-933b-34a88abeda31" xlink:to="loc_us-gaap_StockholdersEquityNoteStockSplitConversionRatio1_019fcdc2-d477-79f2-852e-f0c144b4db09" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedBalanceShares_019fcdc2-d477-7d77-a9b6-d6c0ae51192c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedBalanceShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019fb514-11d0-72c1-933b-34a88abeda31" xlink:to="loc_us-gaap_InvestmentOwnedBalanceShares_019fcdc2-d477-7d77-a9b6-d6c0ae51192c" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights_019fcdc2-d477-7e9f-b213-6ca56bfae3b1" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019fb514-11d0-72c1-933b-34a88abeda31" xlink:to="loc_us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights_019fcdc2-d477-7e9f-b213-6ca56bfae3b1" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_019fcdc2-d477-753c-b417-e2350217857d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019fb514-11d0-72c1-933b-34a88abeda31" xlink:to="loc_us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1_019fcdc2-d477-753c-b417-e2350217857d" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InvestmentOwnedAtFairValue_019fcdc2-d477-7a49-afaa-4979047df07f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentOwnedAtFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019fb514-11d0-72c1-933b-34a88abeda31" xlink:to="loc_us-gaap_InvestmentOwnedAtFairValue_019fcdc2-d477-7a49-afaa-4979047df07f" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_UnrealizedGainLossOnInvestments_019fcdc5-6baf-791a-bf69-48cacfa7e015" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_UnrealizedGainLossOnInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems_019fb514-11d0-72c1-933b-34a88abeda31" xlink:to="loc_us-gaap_UnrealizedGainLossOnInvestments_019fcdc5-6baf-791a-bf69-48cacfa7e015" xlink:type="arc" order="9"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.scotts.com/role/SEGMENTINFORMATIONNetSalesProfitLossandAssetsbySegmentDetails" xlink:type="simple" xlink:href="smg-20260627.xsd#SEGMENTINFORMATIONNetSalesProfitLossandAssetsbySegmentDetails"/>
  <link:definitionLink xlink:role="http://www.scotts.com/role/SEGMENTINFORMATIONNetSalesProfitLossandAssetsbySegmentDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_019e6fc4-5d03-7298-9637-5ffc2719d874" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentReportingInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_019e6fc4-5d03-70a9-96a9-42e082ee55eb" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6fc4-5d03-7298-9637-5ffc2719d874" xlink:to="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_019e6fc4-5d03-70a9-96a9-42e082ee55eb" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_019e6fc4-5d03-7456-ac14-33f64a147ada" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_019e6fc4-5d03-70a9-96a9-42e082ee55eb" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_019e6fc4-5d03-7456-ac14-33f64a147ada" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_019e6fc4-5d03-7456-ac14-33f64a147ada_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_019e6fc4-5d03-7456-ac14-33f64a147ada" xlink:to="loc_us-gaap_SegmentDomain_019e6fc4-5d03-7456-ac14-33f64a147ada_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_019e6fc4-5d03-7575-b9ab-ee471961787a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_019e6fc4-5d03-7456-ac14-33f64a147ada" xlink:to="loc_us-gaap_SegmentDomain_019e6fc4-5d03-7575-b9ab-ee471961787a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_UnitedStatesConsumerSegmentMember_019e6fc4-5d03-7f78-bfb2-31c91366fa4a" xlink:href="smg-20260627.xsd#smg_UnitedStatesConsumerSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_019e6fc4-5d03-7575-b9ab-ee471961787a" xlink:to="loc_smg_UnitedStatesConsumerSegmentMember_019e6fc4-5d03-7f78-bfb2-31c91366fa4a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_U.S.ConsumerMember_019e6fc4-5d03-7787-97af-86cea8f3fc84" xlink:href="smg-20260627.xsd#smg_U.S.ConsumerMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_019e6fc4-5d03-7575-b9ab-ee471961787a" xlink:to="loc_smg_U.S.ConsumerMember_019e6fc4-5d03-7787-97af-86cea8f3fc84" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllOtherSegmentsMember_019e6fc4-5d03-71e6-a270-2286fd691c3a" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AllOtherSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_019e6fc4-5d03-7575-b9ab-ee471961787a" xlink:to="loc_us-gaap_AllOtherSegmentsMember_019e6fc4-5d03-71e6-a270-2286fd691c3a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsAxis_019e6fc4-5d03-7689-9362-d9b579121b7c" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidationItemsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_019e6fc4-5d03-70a9-96a9-42e082ee55eb" xlink:to="loc_srt_ConsolidationItemsAxis_019e6fc4-5d03-7689-9362-d9b579121b7c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_019e6fc4-5d03-7689-9362-d9b579121b7c_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidationItemsAxis_019e6fc4-5d03-7689-9362-d9b579121b7c" xlink:to="loc_srt_ConsolidationItemsDomain_019e6fc4-5d03-7689-9362-d9b579121b7c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_019e6fc4-5d03-7ac7-aa2d-8c103dd23b47" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidationItemsAxis_019e6fc4-5d03-7689-9362-d9b579121b7c" xlink:to="loc_srt_ConsolidationItemsDomain_019e6fc4-5d03-7ac7-aa2d-8c103dd23b47" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingSegmentsMember_019e6fc4-5d03-7940-892d-a7fd546ef1f7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_019e6fc4-5d03-7ac7-aa2d-8c103dd23b47" xlink:to="loc_us-gaap_OperatingSegmentsMember_019e6fc4-5d03-7940-892d-a7fd546ef1f7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CorporateNonSegmentMember_019e6fc4-5d03-77b6-9b5d-693cf7dbd934" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CorporateNonSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_019e6fc4-5d03-7ac7-aa2d-8c103dd23b47" xlink:to="loc_us-gaap_CorporateNonSegmentMember_019e6fc4-5d03-77b6-9b5d-693cf7dbd934" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementOperatingActivitiesSegmentAxis_019e6fc4-5d03-796c-9782-0ef53a88cd9c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementOperatingActivitiesSegmentAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_019e6fc4-5d03-70a9-96a9-42e082ee55eb" xlink:to="loc_us-gaap_StatementOperatingActivitiesSegmentAxis_019e6fc4-5d03-796c-9782-0ef53a88cd9c" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentOperatingActivitiesDomain_019e6fc4-5d03-796c-9782-0ef53a88cd9c_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentOperatingActivitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementOperatingActivitiesSegmentAxis_019e6fc4-5d03-796c-9782-0ef53a88cd9c" xlink:to="loc_us-gaap_SegmentOperatingActivitiesDomain_019e6fc4-5d03-796c-9782-0ef53a88cd9c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentOperatingActivitiesDomain_019e6fc4-5d03-7812-89ce-7518af3ceb59" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentOperatingActivitiesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementOperatingActivitiesSegmentAxis_019e6fc4-5d03-796c-9782-0ef53a88cd9c" xlink:to="loc_us-gaap_SegmentOperatingActivitiesDomain_019e6fc4-5d03-7812-89ce-7518af3ceb59" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentContinuingOperationsMember_019e6fc4-5d03-75a8-b4a4-c724c71d589d" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentContinuingOperationsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentOperatingActivitiesDomain_019e6fc4-5d03-7812-89ce-7518af3ceb59" xlink:to="loc_us-gaap_SegmentContinuingOperationsMember_019e6fc4-5d03-75a8-b4a4-c724c71d589d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_019e6fc4-5d03-7da8-953a-ad08ac565e6f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6fc4-5d03-7298-9637-5ffc2719d874" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_019e6fc4-5d03-7da8-953a-ad08ac565e6f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_CostOfProductAndServiceSoldAdjusted_019e6fc4-5d03-7300-9c66-ec85e915e1c6" xlink:href="smg-20260627.xsd#smg_CostOfProductAndServiceSoldAdjusted"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6fc4-5d03-7298-9637-5ffc2719d874" xlink:to="loc_smg_CostOfProductAndServiceSoldAdjusted_019e6fc4-5d03-7300-9c66-ec85e915e1c6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_SellingGeneralAndAdministrativeExpenseAdjusted_019e6fc4-5d03-795e-9f13-51bc59e99208" xlink:href="smg-20260627.xsd#smg_SellingGeneralAndAdministrativeExpenseAdjusted"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6fc4-5d03-7298-9637-5ffc2719d874" xlink:to="loc_smg_SellingGeneralAndAdministrativeExpenseAdjusted_019e6fc4-5d03-795e-9f13-51bc59e99208" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingOtherItemAmount_019e6fc4-5d03-77ae-a378-45a714181ee7" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentReportingOtherItemAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6fc4-5d03-7298-9637-5ffc2719d874" xlink:to="loc_us-gaap_SegmentReportingOtherItemAmount_019e6fc4-5d03-77ae-a378-45a714181ee7" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_019e6fc4-5d03-7cd9-8255-25e67e4b6d8b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6fc4-5d03-7298-9637-5ffc2719d874" xlink:to="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_019e6fc4-5d03-7cd9-8255-25e67e4b6d8b" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AmortizationOfIntangibleAssets_019e6fc4-5d03-7548-9163-20027180070f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AmortizationOfIntangibleAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6fc4-5d03-7298-9637-5ffc2719d874" xlink:to="loc_us-gaap_AmortizationOfIntangibleAssets_019e6fc4-5d03-7548-9163-20027180070f" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringSettlementAndImpairmentProvisions_019e6fc4-5d03-798e-a4d4-94b524e532ad" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestructuringSettlementAndImpairmentProvisions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6fc4-5d03-7298-9637-5ffc2719d874" xlink:to="loc_us-gaap_RestructuringSettlementAndImpairmentProvisions_019e6fc4-5d03-798e-a4d4-94b524e532ad" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeLossFromEquityMethodInvestments_019e6fc4-5d03-7cbe-ae58-c188dee0c295" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromEquityMethodInvestments"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6fc4-5d03-7298-9637-5ffc2719d874" xlink:to="loc_us-gaap_IncomeLossFromEquityMethodInvestments_019e6fc4-5d03-7cbe-ae58-c188dee0c295" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_InterestExpense_019e6fc4-5d03-7dc6-be6a-ce326c09f0f8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6fc4-5d03-7298-9637-5ffc2719d874" xlink:to="loc_us-gaap_InterestExpense_019e6fc4-5d03-7dc6-be6a-ce326c09f0f8" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherNonoperatingIncomeExpense_019e6fc4-5d03-7e5d-a42c-fa968145af62" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherNonoperatingIncomeExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6fc4-5d03-7298-9637-5ffc2719d874" xlink:to="loc_us-gaap_OtherNonoperatingIncomeExpense_019e6fc4-5d03-7e5d-a42c-fa968145af62" xlink:type="arc" order="9"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.scotts.com/role/SEGMENTINFORMATIONNetSalesbyProductCategoryDetails" xlink:type="simple" xlink:href="smg-20260627.xsd#SEGMENTINFORMATIONNetSalesbyProductCategoryDetails"/>
  <link:definitionLink xlink:role="http://www.scotts.com/role/SEGMENTINFORMATIONNetSalesbyProductCategoryDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems_019e6fc4-5d03-782f-a7a9-a745a6eea108" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable_019e6fc4-5d03-7162-a6c3-011ead209d0b" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems_019e6fc4-5d03-782f-a7a9-a745a6eea108" xlink:to="loc_us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable_019e6fc4-5d03-7162-a6c3-011ead209d0b" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_019e6fc4-5d03-7aa9-aba7-8745e79ab544" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable_019e6fc4-5d03-7162-a6c3-011ead209d0b" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_019e6fc4-5d03-7aa9-aba7-8745e79ab544" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_019e6fc4-5d03-7aa9-aba7-8745e79ab544_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_019e6fc4-5d03-7aa9-aba7-8745e79ab544" xlink:to="loc_us-gaap_SegmentDomain_019e6fc4-5d03-7aa9-aba7-8745e79ab544_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_019e6fc4-5d03-7d2d-b878-565f4a1cb263" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_019e6fc4-5d03-7aa9-aba7-8745e79ab544" xlink:to="loc_us-gaap_SegmentDomain_019e6fc4-5d03-7d2d-b878-565f4a1cb263" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_UnitedStatesConsumerSegmentMember_019e6fc4-5d03-74e8-8515-7d4f2aad798d" xlink:href="smg-20260627.xsd#smg_UnitedStatesConsumerSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_019e6fc4-5d03-7d2d-b878-565f4a1cb263" xlink:to="loc_smg_UnitedStatesConsumerSegmentMember_019e6fc4-5d03-74e8-8515-7d4f2aad798d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllOtherSegmentsMember_019e6fc4-5d03-7000-857e-44e96760c69e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AllOtherSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_019e6fc4-5d03-7d2d-b878-565f4a1cb263" xlink:to="loc_us-gaap_AllOtherSegmentsMember_019e6fc4-5d03-7000-857e-44e96760c69e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_019e6fc4-5d03-7082-b8f9-5f1b7f4f2fc4" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEntityWideInformationRevenueFromExternalCustomersByProductsAndServicesTable_019e6fc4-5d03-7162-a6c3-011ead209d0b" xlink:to="loc_srt_ProductOrServiceAxis_019e6fc4-5d03-7082-b8f9-5f1b7f4f2fc4" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_019e6fc4-5d03-7082-b8f9-5f1b7f4f2fc4_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_019e6fc4-5d03-7082-b8f9-5f1b7f4f2fc4" xlink:to="loc_srt_ProductsAndServicesDomain_019e6fc4-5d03-7082-b8f9-5f1b7f4f2fc4_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_019e6fc4-5d03-72c1-bf54-6c58dbb0b5ec" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_019e6fc4-5d03-7082-b8f9-5f1b7f4f2fc4" xlink:to="loc_srt_ProductsAndServicesDomain_019e6fc4-5d03-72c1-bf54-6c58dbb0b5ec" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_GrowingMediaAndMulchMember_019e6fc4-5d03-7322-98fe-27a6c96df3e7" xlink:href="smg-20260627.xsd#smg_GrowingMediaAndMulchMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_019e6fc4-5d03-72c1-bf54-6c58dbb0b5ec" xlink:to="loc_smg_GrowingMediaAndMulchMember_019e6fc4-5d03-7322-98fe-27a6c96df3e7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_LawnCareMember_019e6fc4-5d03-7555-8d73-1a2ed228c532" xlink:href="smg-20260627.xsd#smg_LawnCareMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_019e6fc4-5d03-72c1-bf54-6c58dbb0b5ec" xlink:to="loc_smg_LawnCareMember_019e6fc4-5d03-7555-8d73-1a2ed228c532" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_ControlsMember_019e6fc4-5d03-7623-af43-4c6bd0ea61dd" xlink:href="smg-20260627.xsd#smg_ControlsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_019e6fc4-5d03-72c1-bf54-6c58dbb0b5ec" xlink:to="loc_smg_ControlsMember_019e6fc4-5d03-7623-af43-4c6bd0ea61dd" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_RoundupMarketingAgreementMember_019e6fc4-5d03-75b8-aa0c-9341d9c09456" xlink:href="smg-20260627.xsd#smg_RoundupMarketingAgreementMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_019e6fc4-5d03-72c1-bf54-6c58dbb0b5ec" xlink:to="loc_smg_RoundupMarketingAgreementMember_019e6fc4-5d03-75b8-aa0c-9341d9c09456" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_OtherProductsPrimarilyGardeningMember_019e6fc4-5d03-7255-b670-32fe8c93051c" xlink:href="smg-20260627.xsd#smg_OtherProductsPrimarilyGardeningMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_019e6fc4-5d03-72c1-bf54-6c58dbb0b5ec" xlink:to="loc_smg_OtherProductsPrimarilyGardeningMember_019e6fc4-5d03-7255-b670-32fe8c93051c" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_GrowingmediaMember_019e6fc4-5d03-7cca-b0b4-2e951d07f5f4" xlink:href="smg-20260627.xsd#smg_GrowingmediaMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_019e6fc4-5d03-72c1-bf54-6c58dbb0b5ec" xlink:to="loc_smg_GrowingmediaMember_019e6fc4-5d03-7cca-b0b4-2e951d07f5f4" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_OtherprimarilygardeningandcontrolsMember_019e6fc4-5d03-7390-bd8e-41dd4aa89da2" xlink:href="smg-20260627.xsd#smg_OtherprimarilygardeningandcontrolsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ProductsAndServicesDomain_019e6fc4-5d03-72c1-bf54-6c58dbb0b5ec" xlink:to="loc_smg_OtherprimarilygardeningandcontrolsMember_019e6fc4-5d03-7390-bd8e-41dd4aa89da2" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_019e6fc4-5d03-762b-b708-bdf28779008c" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EntityWideInformationRevenueFromExternalCustomerLineItems_019e6fc4-5d03-782f-a7a9-a745a6eea108" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_019e6fc4-5d03-762b-b708-bdf28779008c" xlink:type="arc" order="0"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.scotts.com/role/SEGMENTINFORMATIONOtherSegmentDisclosuresDetails" xlink:type="simple" xlink:href="smg-20260627.xsd#SEGMENTINFORMATIONOtherSegmentDisclosuresDetails"/>
  <link:definitionLink xlink:role="http://www.scotts.com/role/SEGMENTINFORMATIONOtherSegmentDisclosuresDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_019e6fc4-5d03-7fe4-8727-ed55c2fe2744" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentReportingInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_019e6fc4-5d03-7664-b1a4-fc65375f1a86" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6fc4-5d03-7fe4-8727-ed55c2fe2744" xlink:to="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_019e6fc4-5d03-7664-b1a4-fc65375f1a86" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsAxis_019e6fc4-5d03-766b-a371-954df13ec0b1" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidationItemsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_019e6fc4-5d03-7664-b1a4-fc65375f1a86" xlink:to="loc_srt_ConsolidationItemsAxis_019e6fc4-5d03-766b-a371-954df13ec0b1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_019e6fc4-5d03-766b-a371-954df13ec0b1_default" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidationItemsAxis_019e6fc4-5d03-766b-a371-954df13ec0b1" xlink:to="loc_srt_ConsolidationItemsDomain_019e6fc4-5d03-766b-a371-954df13ec0b1_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_019e6fc4-5d03-75da-a6d3-1f593718a0dc" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidationItemsAxis_019e6fc4-5d03-766b-a371-954df13ec0b1" xlink:to="loc_srt_ConsolidationItemsDomain_019e6fc4-5d03-75da-a6d3-1f593718a0dc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingSegmentsMember_019e6fc4-5d03-7318-86be-e87896104f56" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_019e6fc4-5d03-75da-a6d3-1f593718a0dc" xlink:to="loc_us-gaap_OperatingSegmentsMember_019e6fc4-5d03-7318-86be-e87896104f56" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_019e6fc4-5d03-76fa-97fc-c492ea54498f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_019e6fc4-5d03-7664-b1a4-fc65375f1a86" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_019e6fc4-5d03-76fa-97fc-c492ea54498f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_019e6fc4-5d03-76fa-97fc-c492ea54498f_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_019e6fc4-5d03-76fa-97fc-c492ea54498f" xlink:to="loc_us-gaap_SegmentDomain_019e6fc4-5d03-76fa-97fc-c492ea54498f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_019e6fc4-5d03-7ceb-a7be-65d291bee612" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_019e6fc4-5d03-76fa-97fc-c492ea54498f" xlink:to="loc_us-gaap_SegmentDomain_019e6fc4-5d03-7ceb-a7be-65d291bee612" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_U.S.ConsumerMember_019e6fc4-5d03-7585-b07a-73aa29caeeaa" xlink:href="smg-20260627.xsd#smg_U.S.ConsumerMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_019e6fc4-5d03-7ceb-a7be-65d291bee612" xlink:to="loc_smg_U.S.ConsumerMember_019e6fc4-5d03-7585-b07a-73aa29caeeaa" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepreciationAndAmortization_019e6fc4-5d03-7e35-bab1-6a3f00321940" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DepreciationAndAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6fc4-5d03-7fe4-8727-ed55c2fe2744" xlink:to="loc_us-gaap_DepreciationAndAmortization_019e6fc4-5d03-7e35-bab1-6a3f00321940" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllocatedShareBasedCompensationExpense_019e6fc4-5d03-7b53-ac22-53ed86058709" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AllocatedShareBasedCompensationExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6fc4-5d03-7fe4-8727-ed55c2fe2744" xlink:to="loc_us-gaap_AllocatedShareBasedCompensationExpense_019e6fc4-5d03-7b53-ac22-53ed86058709" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.scotts.com/role/SEGMENTINFORMATIONNetSalesbyGeographicAreaDetails" xlink:type="simple" xlink:href="smg-20260627.xsd#SEGMENTINFORMATIONNetSalesbyGeographicAreaDetails"/>
  <link:definitionLink xlink:role="http://www.scotts.com/role/SEGMENTINFORMATIONNetSalesbyGeographicAreaDetails" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_019e6fc4-5d03-7bd0-91b6-e37ef78b28d8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentReportingInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_019e6fc4-5d03-7986-a886-f74ae0c89a4e" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6fc4-5d03-7bd0-91b6-e37ef78b28d8" xlink:to="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_019e6fc4-5d03-7986-a886-f74ae0c89a4e" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_019e6fc4-5d03-7b23-975f-208000ae6166" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_019e6fc4-5d03-7986-a886-f74ae0c89a4e" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_019e6fc4-5d03-7b23-975f-208000ae6166" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_019e6fc4-5d03-7b23-975f-208000ae6166_default" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_019e6fc4-5d03-7b23-975f-208000ae6166" xlink:to="loc_us-gaap_SegmentDomain_019e6fc4-5d03-7b23-975f-208000ae6166_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_019e6fc4-5d03-7a4a-bbe7-079c5785b0f8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_019e6fc4-5d03-7b23-975f-208000ae6166" xlink:to="loc_us-gaap_SegmentDomain_019e6fc4-5d03-7a4a-bbe7-079c5785b0f8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_smg_UnitedStatesConsumerSegmentMember_019e6fc4-5d03-750f-a894-1908ccc5b494" xlink:href="smg-20260627.xsd#smg_UnitedStatesConsumerSegmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_019e6fc4-5d03-7a4a-bbe7-079c5785b0f8" xlink:to="loc_smg_UnitedStatesConsumerSegmentMember_019e6fc4-5d03-750f-a894-1908ccc5b494" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllOtherSegmentsMember_019e6fc4-5d03-711b-a8ac-b51a995d1be8" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AllOtherSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_019e6fc4-5d03-7a4a-bbe7-079c5785b0f8" xlink:to="loc_us-gaap_AllOtherSegmentsMember_019e6fc4-5d03-711b-a8ac-b51a995d1be8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_019e6fc4-5d03-78d9-9282-d5f9e535af0f" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_019e6fc4-5d03-7bd0-91b6-e37ef78b28d8" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax_019e6fc4-5d03-78d9-9282-d5f9e535af0f" xlink:type="arc" order="0"/>
  </link:definitionLink>
</link:linkbase>
