Colorado

Colorado Constitution art. XVIII, § 16 (Amendment 64) makes it lawful for adults 21+ to possess, grow up to six plants (three flowering), and transfer up to one ounce or six immature plants to another adult without remuneration — seeds are within the constitutional definition of marijuana. Licensed retail marijuana stores and cultivations may sell seeds and immature plants to consumers under the Marijuana Enforcement Division's Retail Marijuana Rules (1 CCR 212-3). Hemp growers must register with the Colorado Department of Agriculture under C.R.S. Title 35, Article 61, but viable hemp seed is freely bought and sold as agricultural seed.