IMPAIRMENT, RESTRUCTURING AND OTHER - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		27 Months Ended
	Dec. 30, 2023	Dec. 31, 2022	Dec. 30, 2023
Restructuring Cost and Reserve [Line Items]
Restructuring reserve, long-term	$ 13.8		$ 13.8
Employee Severance and Impairment Of Property, Plant, And Equipment
Restructuring Cost and Reserve [Line Items]
Restructuring charges and adjustments	(3.7)	$ 14.5
Hawthorne
Restructuring Cost and Reserve [Line Items]
Restructuring charges and adjustments			217.1
U.S. Consumer
Restructuring Cost and Reserve [Line Items]
Restructuring charges and adjustments			46.7
Corporate Segment
Restructuring Cost and Reserve [Line Items]
Restructuring charges and adjustments			25.1
Other
Restructuring Cost and Reserve [Line Items]
Restructuring charges and adjustments			$ 1.6
Cost of sales—impairment, restructuring and other \| Hawthorne
Restructuring Cost and Reserve [Line Items]
Restructuring charges and adjustments	(7.7)	8.4
Cost of sales—impairment, restructuring and other \| U.S. Consumer
Restructuring Cost and Reserve [Line Items]
Restructuring charges and adjustments	2.0	1.0
Impairment, Restructuring, And Other
Restructuring Cost and Reserve [Line Items]
Gain (loss) on resolution of dispute	12.1
Impairment, Restructuring, And Other \| Hawthorne
Restructuring Cost and Reserve [Line Items]
Restructuring charges and adjustments	0.3	1.0
Impairment, Restructuring, And Other \| U.S. Consumer
Restructuring Cost and Reserve [Line Items]
Restructuring charges and adjustments	(0.8)	0.2
Impairment, Restructuring, And Other \| Corporate Segment
Restructuring Cost and Reserve [Line Items]
Restructuring charges and adjustments	$ 2.4	3.8
Impairment, Restructuring, And Other \| Other
Restructuring Cost and Reserve [Line Items]
Restructuring charges and adjustments		$ 0.1