How Many Weed Plants Can You Grow in Colorado?

In Colorado, adults 21 and older can grow up to six marijuana plants at home for personal use, with no more than three of those plants flowering at any given time.¹ A single residence tops out at 12 plants total, no matter how many eligible adults live there.²

The Household Cap Catches People Off Guard

Six plants per adult sounds straightforward until you add roommates. Three eligible adults sharing a house do not get 18 plants between them. They still share a 12-plant ceiling.² This is the detail that trips up shared households most often, and it applies regardless of whether each grower keeps their plants in a separate room.

What Actually Counts as a Plant

Colorado’s definition gives you a little room at the front end of a grow cycle. A “plant” only means cannabis in a growing medium that is more than four inches tall or four inches wide, or any flowering plant regardless of size.² Fresh clones and small seedlings that fall below that size threshold do not count toward your six or the household’s 12. Once anything begins flowering, the size exemption disappears.

Medical Patients Can Grow More With Documentation

Registered medical marijuana patients start with the same six-plant, three-flowering baseline. A patient or their primary caregiver can qualify to grow up to 24 plants when a physician determines the higher count is medically necessary for that patient’s condition.² The exception is written into the cultivation statute and requires documentation tying the higher count to the patient’s medical needs. Twenty-four is the residential ceiling unless a local government has expressly authorized more.

Where You Can Grow

Every home grow in Colorado has to be kept in an enclosed, locked space that is not visible from outside. Outdoor cultivation is not permitted.¹ A spare bedroom, closet, basement, or garage all work as long as the space can be secured.

What “locked” means depends on who lives there. If everyone in the home is 21 or older, the home’s exterior locks are enough. If anyone under 21 lives at the address, the grow area itself has to be separately enclosed and locked so minors cannot access it. The same standard applies whenever anyone under 21 is visiting.²

If you rent, your landlord can prohibit home cultivation even though state law allows it. State law does not override a property owner’s authority to set rules for their units, and a landlord who discovers an unauthorized grow has grounds for eviction regardless of your plant count.

Your City or County Can Change the Numbers

Colorado’s plant limits are a baseline. Local governments can pass stricter ordinances that reduce plant counts below 12 or ban home growing entirely.¹ Denver, for example, caps home grows at 12 plants even in households with three or more adults.

The statute also lets local governments expressly permit more than 12 plants at a residence, provided the grower stays within the local limit and keeps the grow enclosed and locked.² Most municipalities have kept the 12-plant cap or tightened it rather than loosening. Check your city and county codes before setting up.

Federal Housing and Federal Land Are Off Limits

Marijuana is still a Schedule I substance under federal law, and that matters in two situations Colorado growers sometimes assume state law covers.

If you live in federally subsidized housing, including Section 8 or public housing, growing cannabis at home can lead to eviction. Federal housing policy prohibits marijuana possession and cultivation in federally assisted property regardless of state legalization.

Federal property inside Colorado follows federal law. National forests, military installations, and Bureau of Land Management land are all federal jurisdiction, and cultivating cannabis there exposes you to federal drug manufacturing charges.

Penalties for Going Over the Limit

Colorado handles violations of the residential plant cap on a sliding scale, and the jump from a first offense to a repeat is severe.

First offense with more than 12 plants: a Level 1 drug petty offense, punishable by a fine of up to $1,000. No jail time.²
Second or subsequent offense with 13 to 24 plants: a Level 1 drug misdemeanor, carrying six to 18 months in county jail and fines from $500 to $5,000.³
Second or subsequent offense with more than 24 plants: a Level 3 drug felony, with a presumptive prison range of two to four years and fines from $2,000 to $500,000. An aggravated sentence can push the prison term to six years.⁴

Courts also have discretion to impose up to one year of parole after a Level 3 drug felony sentence.⁴

1
Colorado Cannabis. Home Grow Laws
2
FindLaw. Colorado Code 18-18-406 – Offenses Relating to Marijuana and Marijuana Concentrate
3
FindLaw. Colorado Code 18-1.3-501 – Misdemeanor Sentencing and Penalties
4
Justia Law. Colorado Code 18-1.3-401.5 – Drug Felony Sentencing