Recreational marijuana can’t be grown outdoors legally in Colorado, so people grow it indoors instead.
Indoor grows require vast horticultural knowledge and many homeowners aren’t up to the task. They encounter common problems like airborne mold spores, electrical hazards, and jerry-rigged home modifications.
Below, our restoration professionals discuss what you should be aware of to grow marijuana safely (and legally!) inside a home.
Grow Rules & Safety Standards
Home grow laws in Colorado stipulate where and how many marijuana plants can be grown in a private residence. Specifically, marijuana plants must be grown in an enclosed space with working locks and hidden from public view—in other words, no pot plants outside.
Coloradans can grow up to six plants per resident over the age of 21, with as many as three plants flowering at any given time. Home growers are limited to a maximum of 12 plants, even if multiple home residents are over the age of 21.
Counties and municipalities may pass stricter laws. It’s up to each grower to know and follow the laws of their jurisdiction.
Like all plants, marijuana needs water and sunlight to flourish. To mimic outdoor conditions, growers expose their interiors to moisture, heat, and dangerously high electrical demands.
While not ideal for protecting your home investment, it’s possible to grow marijuana inside without causing irreversible damage. Here’s how:
Indoor growers use a range of lighting systems to cultivate healthy plants. The grow’s size, setup, and the grower’s financial resources will dictate what type of lighting works best.
Regardless, it’s essential to seek a licensed electrician to prevent fire hazards. A professional can verify wiring and electrical systems can handle the grow systems intense demands.
Some growers prefer to grow their plants hydroponically (in water; without soil). This poses obvious risks combined with a heavy electrical output.
All electrical equipment should be fastened and secured off the ground.
Temperature and humidity are important factors in the cultivation process. These two factors fluctuate over the course of the growth cycle, but generally, ideal temperatures range from 70 to 82 degrees with a relative humidity level as high as 70 percent.
Ideal growing conditions do not equal ideal home conditions, and without proper ventilation and other mitigation techniques, home mold and mildew are likely.
Too much humidity can also result in a powdery mildew on the plants, a common and tenacious pathogen that can be dangerous to people combined with other growing conditions.
Poor air quality can result in significant health problems, particularly for those with asthma and other respiratory sensitivities.
To avoid excess humidity, cool air must flow into the grow room, and hot air must flow out. At the very least, growers will need an intake fan, exhaust fan, ducting, and duct tape.
If possible, growers should also consider encapsulating the grow room in waterproof polyethylene (plastic sheeting). Drywall continuously exposed to moisture can grow mold behind walls and under baseboards. Encapsulation may prevent long-term deterioration and may also improve general growing conditions.
There’s no one-size-fits-all solution for the retrofit design of a home grow room. Safety and home preservation are critical, however, especially if the property is ever sold or rented.
Colorado brokers, for example, are required to disclose adverse material facts about a home, which includes issues like mold and mildew that may arise from growing marijuana inside; this could turn away potential buyers.