Why it matters
The Agriculture Improvement Act of 2018 (commonly the “Farm Bill”) legalised hemp cultivation under USDA supervision and defined hemp by delta-9-THC content. The legislation opened the federal CBD market, enabled industrial hemp cultivation, and unintentionally opened the regulatory door to hemp-derived intoxicants like delta-8 and HHC.
In practice
For consumers the practical effect was the explosion of the CBD retail category in 2019–2020. For regulators it created a moving target: the bill’s focus on delta-9 left gaps that the industry has filled with novel cannabinoids the bill’s authors did not anticipate.
Common confusion
The Farm Bill is sometimes characterised as “legalising hemp THC.” It legalised hemp containing trace delta-9; the legality of synthesised hemp-derived intoxicants is more contested.
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