Is It Legal to Grow Cannabis at Home in Montana? (2026 Rules)

Jurisdiction: Montana  |  Last verified: September 4, 2026  |  Program: Adult personal cultivation

Quick answer: Yes. A Montana adult age 21 or older may grow up to two mature cannabis plants and two seedlings at a private residence. A single residence may contain no more than twice that adult-use amount at one time: four mature plants and four seedlings.

Montana home-grow rules in plain language

• Minimum age: 21.
• Per-person mature limit: two plants.
• Per-person seedling limit: two seedlings.
• Residence limit: four mature plants and four seedlings at one time for adult personal use.
• Location: in or on the grounds of a private residence.
• Security: plants and homegrown cannabis above one ounce must be kept in a locked space.
• Public view: the grow cannot be visible by normal unaided vision from a public place.
• Property permission: the grower must own the residence or obtain the owner’s written permission.

How Montana defines the plant categories

A mature marijuana plant is a harvestable plant. A seedling is a plant with no flowers that is less than 12 inches high and less than 12 inches in diameter. Track size and flowering status because a plant can leave the seedling category before it becomes harvestable.

The residence limit is twice the personal limit

One qualifying adult may grow two mature plants and two seedlings. When multiple qualifying adults share the residence, the property may contain no more than four mature plants and four seedlings at the same time.

Owner permission must be written

A grower who does not own the private residence must obtain written permission from the owner to cultivate and store marijuana there. The personal grow area also cannot be shared with, rented to or leased to a marijuana business.

Before you start

1. Confirm property rights. Obtain the owner’s written permission when the grower is not the owner.
2. Count by category. Track seedlings and mature plants separately.
3. Count the residence. Stay within the four-mature/four-seedling shared cap.
4. Lock the grow and harvest. Prevent unauthorized access.
5. Block public view. Check the grow from every public sight line.

Official Montana sources

• Montana Code Annotated § 16-12-106
• Montana Code Annotated § 16-12-102: Definitions

Ready to learn the cultivation side?

After the owner permission, lock and plant counts meet Montana’s rules, use the HWGrow complete beginner guide for a practical seed-to-harvest workflow.

Compare Montana with the HWGrow U.S. cannabis home-grow law guide.

Montana home-grow FAQ

How many cannabis plants may one Montana adult grow?

An adult age 21 or older may grow up to two mature plants and two seedlings at a private residence.

What is the Montana residence plant limit?

A private residence may contain no more than four mature plants and four seedlings at one time for adult personal use.

May a Montana renter grow cannabis?

Only with the residence owner’s written permission. The plants and homegrown cannabis above one ounce must also be locked and outside public view.