Cover - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Mar. 01, 2023	Jun. 30, 2022
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2022
Current Fiscal Year End Date	--12-31
Document Transition Report	false
Entity File Number	001-39773
Entity Registrant Name	Hydrofarm Holdings Group, Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	81-4895761
Entity Address, Address Line One	1510 Main Street
Entity Address, City or Town	Shoemakersville
Entity Address, State or Province	PA
Entity Address, Postal Zip Code	19555
City Area Code	707
Local Phone Number	765-9990
Title of 12(b) Security	Common Stock, $0.0001 par value per share
Trading Symbol	HYFM
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Entity Public Float			$ 148
Entity Common Stock, Shares Outstanding		45,258,497
Documents Incorporated by Reference	Portions of the registrant’s Proxy Statement for its 2023 Annual Meeting of Stockholders are incorporated by reference into Part III of this Annual Report on Form 10-K to the extent stated herein. Such Proxy Statement will be filed with the Securities and Exchange Commission within 120 days of the registrant’s fiscal year ended December 31, 2022.
Amendment Flag	false
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	FY
Entity Central Index Key	0001695295