| Document and Entity Information Document | Aug. 04, 2021 |
| Entity Information [Line Items] | |
| Amendment Flag | false |
| Entity Emerging Growth Company | false |
| Pre-commencement Issuer Tender Offer | false |
| Pre-commencement Tender Offer | false |
| Soliciting Material | false |
| Written Communications | false |
| Security Exchange Name | NYSE |
| Trading Symbol | SMG |
| Title of 12(b) Security | Common Shares, $0.01 stated value |
| Local Phone Number | 644-0011 |
| City Area Code | 937 |
| Entity Address, Postal Zip Code | 43041 |
| Entity Address, State or Province | OH |
| Entity Address, City or Town | Marysville |
| Entity Address, Address Line One | 14111 Scottslawn Road |
| Entity Tax Identification Number | 31-1414921 |
| Entity File Number | 001-11593 |
| Entity Incorporation, State or Country Code | OH |
| Entity Registrant Name | Scotts Miracle-Gro Co |
| Document Type | 8-K |
| Document Period End Date | Aug. 4, 2021 |
| Entity Central Index Key | 0000825542 |
