HEMP CULTIVATION & LAND USE

Hemp cultivation in California sits at the intersection of CDFA regulatory compliance, county agricultural zoning, Williamson Act contract obligations, State Water Board permitting, and federal Farm Bill requirements — a regulatory framework that is entirely separate from the DCC cannabis licensing system and that has evolved significantly since the 2018 federal legalization of hemp. The Law Office of Shay Aaron Gilmore guides hemp cultivators, agricultural landowners, and investors through CDFA Industrial Hemp Program registration, county agricultural commissioner requirements, zoning compliance, Williamson Act analysis, and water rights and environmental compliance across California’s diverse agricultural regions.

The firm serves cultivators, distributors, manufacturers, testing labs, retailers, investors, landowners, and management companies operating in both cannabis and hemp markets, providing coordinated advice for the growing number of dual-license operators holding DCC cannabis licenses and CDFA hemp registrations simultaneously. Named as one of the Top 20 Cannabis Lawyers in California by the Los Angeles/San Francisco Daily Journal, recognized among the Top 200 Global Cannabis Lawyers by Cannabis Law Journal, and listed among the Top 100 Lawyers in Northern California by Super Lawyers® Magazine, Shay Aaron Gilmore serves as a Board Member of the International Cannabis Bar Association (INCBA), Founder of the Cannabis Practitioners Group of the California Lawyers Association, and Co-Founder of the Cannabis Law Section of the Bar Association of San Francisco.

Recognized By

CDFA Industrial Hemp Registration: What California Cultivators Need to Know

California hemp cultivators are regulated under the California Industrial Hemp Program administered by the California Department of Food and Agriculture (CDFA), pursuant to California’s USDA-approved State Regulatory Plan for Hemp Production under the 2018 federal Farm Bill. Registration is required before planting — no hemp may be legally cultivated without a valid CDFA registration and county agricultural commissioner registration.

CDFA Registration Requirements.

A complete CDFA grower registration requires:

A completed application submitted through the CDFA’s online portal
GPS coordinates identifying the precise location and boundaries of the cultivation site
Identification of the hemp variety or varieties to be cultivated, including documentation that the variety is on the USDA’s approved hemp seed list or that THC testing under 0.3% has been established
Payment of the $900 annual registration fee
A criminal history report for all “key participants” — defined as sole proprietors, general partners, executive officers, and persons who direct management and policy decisions

County Agricultural Commissioner Requirements.

In addition to CDFA registration, hemp cultivators must register with the county agricultural commissioner in the county where cultivation occurs. County-level requirements supplement state requirements and vary by county — some counties impose additional notification or reporting obligations.

Annual Renewal.

Hemp registrations are valid for one year from the date of issuance. Renewal requires submission of a new application and $900 fee to the county agricultural commissioner at least 30 calendar days before expiration. If the renewal application is received less than 30 days before expiration and the registration is not renewed before it expires, any existing plantings are considered noncompliant and subject to destruction. Unlike cannabis license lapses, a lapsed hemp registration can result in the loss of an entire standing crop with no grace period.

THC Testing and Compliance.

All hemp cultivators must arrange for pre-harvest THC testing of each lot by a USDA-approved laboratory. Any lot testing at or above 0.3% THC on a dry weight basis is considered “hot” cannabis — not hemp — and is subject to destruction. Cultivators must maintain records of all testing and sampling and make them available to the CDFA and county agricultural commissioner on request.

Agricultural Land Use and the Williamson Act

The California Land Conservation Act of 1965 — commonly known as the Williamson Act — allows landowners to enter into voluntary contracts with counties restricting their land to agricultural or compatible open-space use in exchange for reduced property tax assessments based on agricultural value rather than market value. Approximately 16 million acres of California farmland — including a substantial portion of the state’s premier cannabis and hemp cultivation regions — is currently enrolled in the Williamson Act program.

Is Hemp Cultivation Compatible with Williamson Act Land?

Hemp cultivation is generally compatible with Williamson Act agricultural use restrictions because hemp is an agricultural crop regulated by the CDFA as an agricultural commodity. A county board of supervisors, acting as the landowner’s Williamson Act contracting partner, may issue a compatibility determination confirming that a proposed use is consistent with the agricultural use restriction. Most counties treat hemp cultivation on Williamson Act land as presumptively compatible without requiring a formal compatibility determination

When Compatibility Determinations Are Required.

Proposed uses that go beyond simple field cultivation may require a formal compatibility determination from the county board of supervisors before proceeding:

On-site hemp processing facilities or extraction operations
Storage or warehouse facilities not incidental to cultivation
Employee housing on the agricultural parcel
Infrastructure improvements not typically associated with open-field cultivation

Cancellation Risks.

A landowner who proposes a use that a county determines is incompatible with the Williamson Act contract — or who proceeds with an incompatible use without a compatibility determination — risks Williamson Act contract cancellation. Cancellation triggers a penalty equal to 12.5% of the full fair-market value of the land, paid over nine years. For high-value agricultural parcels in premium hemp-growing regions, the cancellation penalty can be substantial.

Non-Renewal vs. Cancellation.

Williamson Act contracts automatically renew annually unless notice of non-renewal is filed. Non-renewal does not trigger a penalty but results in the contract running out over its remaining term (typically 10 years). Landowners considering hemp or cannabis uses that may be incompatible should evaluate non-renewal as an alternative to cancellation where the timeline permits.

For land use issues related to cannabis (rather than hemp) on agricultural parcels, see Cannabis Zoning & Conditional Use Permits. For CDFA and DCC regulatory compliance across both hemp and cannabis programs, see Regulatory Compliance.

Cannabis vs. Hemp: Land Use and Regulatory Framework

Hemp and cannabis are the same plant species, but their land use and regulatory frameworks in California are so different that they effectively operate as two separate industries:

	Cannabis	Hemp
Regulator	Department of Cannabis Control	CA Dept. of Food and Agriculture
Registration/Licensing	State annual license (DCC) + local permit	CDFA state registration + county ag commissioner registration
Zoning	Industrial, commercial, or cannabis-specific zones in most jurisdictions	Agricultural zones (A-1, A-2, AG, etc.) — hemp is an agricultural crop
Local ban authority	Yes — jurisdictions may ban commercial cannabis entirely	Limited — municipalities generally cannot ban agricultural cultivation
Sensitive use setbacks	Yes — 600 ft. from schools minimum; local ordinances often higher	Not applicable
Williamson Act	Generally incompatible with cannabis cultivation on Williamson Act land	Generally compatible — hemp is an agricultural crop
CEQA	Required for all new CUP applications	May apply to large-scale operations; categorical exemptions available
Water rights	SWRCB permits may be required for water diversion	SWRCB permits may be required for water diversion
Pre-harvest testing	Not required (post-harvest testing for product compliance)	Required for THC compliance — lots above 0.3% THC must be destroyed
Annual registration fee	Varies by license type (hundreds to thousands of dollars)	$900 flat fee
Co-location with cannabis	FAC §81006 restricts hemp on DCC-licensed cannabis premises without DCC approval	Hemp cultivation on premises that overlap with a DCC cannabis license requires DCC authorization

For supply chain contracting for hemp cultivation and processing operations, see Commercial Contracts. For hemp business entity formation and CDFA regulatory compliance, see Corporate Law and Regulatory Compliance.

Representative Matters

Guided an agricultural landowner in the San Joaquin Valley through CDFA hemp registration, county agricultural commissioner registration, and a Williamson Act compatibility determination for proposed on-site hemp processing infrastructure on Williamson Act-enrolled farmland
Advised a prospective dual-license hemp and cannabis cultivator in the North Coast region on coordinating CDFA hemp registration and DCC cultivation license requirements for an operation spanning two adjacent parcels — one enrolled in the Williamson Act and one outside the program — and on the FAC §81006 same-premises analysis
Assisted a San Joaquin Valley hemp cultivator whose lot tested above 0.3% THC on a pre-harvest CDFA test, coordinating with the CDFA and county agricultural commissioner to document the required lot destruction and preserve the cultivator’s registration in good standing for the following growing season

Frequently Asked Questions

Q1: Do hemp cultivators in California need to register with the CDFA?

Yes. Under the California Industrial Hemp Program, all hemp cultivators must register with the CDFA before planting. Registration requires a completed application, GPS coordinates for the cultivation site, hemp variety identification, a $900 annual fee, and criminal history reports for all key participants. County agricultural commissioner registration is also required. Cultivating without a valid registration can result in the cultivation being classified as illegal cannabis, subject to law enforcement action.

Q2: How does California's Williamson Act affect hemp cultivation?

Hemp cultivation is generally compatible with Williamson Act agricultural use restrictions, and most counties do not require a formal compatibility determination for field hemp cultivation alone. However, proposed processing facilities, non-agricultural structures, or significant infrastructure improvements on Williamson Act land may require a county compatibility determination before construction proceeds. Landowners who proceed with incompatible uses without a determination risk Williamson Act contract cancellation, which triggers a penalty of 12.5% of full fair-market land value paid over nine years.

Q3: What water rights issues arise for California hemp cultivators?

Cultivators diverting water from streams, rivers, or groundwater sources may need a permit or license from the State Water Resources Control Board. Cultivators with pre-1914 appropriative rights or riparian rights may have existing entitlements but must confirm the scope of those entitlements for a new cultivation use. The SWRCB and regional water quality control boards also regulate agricultural discharges. Any new hemp cultivation site requires a site-specific water rights and discharge analysis before operations begin.

Q4: Can hemp be processed or extracted on the cultivation site in California?

On-site hemp processing is permitted but typically requires separate land use approvals — including use permits or conditional use permits under county zoning codes — beyond those needed for cultivation alone. CDFA regulates hemp processors separately from cultivators, and a separate processor registration is required for on-site extraction and manufacturing. Extraction operations involving flammable solvents may also require fire department approval and fire code compliance. For Williamson Act-enrolled properties, on-site processing may require a compatibility determination.

Q5: How does California's state hemp program relate to the federal Farm Bill?

California hemp is regulated under the CDFA’s California Industrial Hemp Program pursuant to California’s USDA-approved State Regulatory Plan for Hemp Production under the 2018 federal Farm Bill. Hemp is defined under both state and federal law as cannabis with less than 0.3% THC on a dry weight basis. California’s state plan includes requirements that go beyond federal minimum standards. Both state and federal law apply to California hemp cultivators, and the regulatory landscape continues to evolve as federal and state hemp regulations are revised.

Helpful Resources & Related Pages

Explore related licensing, compliance, and legal services

Locations Served

Related Real Estate & Land Use Pages

Cannabis Zoning & Conditional Use Permits

How cannabis operators secure local CUPs and navigate setback requirements before committing to a site.

Cannabis Commercial Lease Negotiation

How cannabis operators negotiate leases with licensing contingencies and DCC-compliant assignment provisions.

Cannabis Real Estate Due Diligence

How buyers and investors conduct DCC license verification, title review, and environmental assessment before closing.