Plants need fresh air to thrive and carbon dioxide (CO2) is essential to the process of photosynthesis. This means you will need a steady stream of air flowing through your grow room, which will allow you to move hot air out of the space and bring cool air in.
Soil is the most traditional medium for growing marijuana indoors, as well as the most forgiving, making it a good choice for first-time growers. Any high-quality potting soil will work, as long as it doesn’t contain artificial extended release fertilizer—like Miracle Gro—which is unsuitable for growing good cannabis.
LED grow lights
Fans should be positioned to provide direct, even airflow throughout the garden. This typically involves using multiple fans that work together or fans that have oscillation capabilities.
Finding the right soil for cannabis
As your plants get bigger and especially when they start flowering, they’ll start to smell more. Outfitting your grow with a dehuey or AC can help bring odor down.
Since clones come from plants that have been grown indoors, let yours chill in a shaded area for a week before exposing them to full sun, Johnson says. “The clone hasn’t tasted sun like that, and the transplant itself will be stressful.”
Do your homework and read up on the laws in your state. Some states prohibit growing cannabis, while others, like my home state of California, permits anyone over age 21 to grow cannabis, but only up to a certain number of plants. NORML has a pretty in-depth guide to the laws in each state. Colorado, Oregon, Nevada, Vermont, and Maine also allow cultivation, but again, the specifics depend on the state. Definitely clarify what your rights are before you start the glorious path to at-home bud gardening.
Don’t go overboard, though, he warns. Start with growing three plants in five-gallon pots. This way, if one dies, you’ll still have two plants, and the pots will limit their growth. A general rule of thumb is that they’ll grow one foot for every gallon of soil. He recommends mixing your own organic soil, which he explains how to do on his website and will save you the headache of adding nutrients or pH testing. “The soil is what we call alive,” he says. “It’s always breaking things down to replenish nutrients that are missing.” But if you can’t mix your own soil, or don’t feel like it, you could buy organic Pro-Mix soil, which Johnson says many outdoor growers use.
If you buy seeds from a seed bank, look for those labeled “feminized” to ensure they give rise to female plants, Johnson says. But if you’re a total newbie, he suggests buying clones, which are cuttings from a “mother” female plant, available at some dispensaries, as well as at nurseries. Not only are they easier to obtain, “they’re easier to grow. You get a clone, and you transplant it to some soil.”
While you can absolutely grow cannabis indoors, outdoor cultivation is much simpler and cheaper, says Ron Johnson, author of How to Grow Organic Cannabis: A Step-by-Step Guide for Growing Marijuana Outdoors, who also runs the website The Cannabis Gardener. “The sun is free,” he tells Mic. “You don’t have to pay hundreds of dollars a month in electrical bills.” An outdoor garden probably won’t allow you to turn over product fast enough, but it’ll suffice if you just want to grow weed for yourself. Plus, it’s gentler on the planet.
Before you get started
Cannabis cultivation laws vary widely state-by-state. Also, we can’t stress this enough: Growing cannabis is illegal in a lot of places, and the penalties — which include steep fines and prison time — can be much worse than possession, since growing can imply an intent to distribute. Black and brown folx need to be especially scrupulous about heeding these rules, since law enforcement targets us way more than white people for weed-related charges, even if we consume it at similar rates.
Whatever you do, don’t plant your clones in the ground. They’ll run rampant, and “you’ll have pounds of weed in your house,” Johnson says, recalling the trays of weed atop his kitchen table when his crop grew wild. “You don’t need the stress of plants getting out of control, growing over your fence.” If your neighbors can see them, they might complain about them, and having too many plants could get you arrested.
Grow tents also make it easier for home growers to maintain two separate environments: one for vegetative growth, and the other for flowering. This allows you to keep a perpetual harvest going by propagating and growing young plants in one tent and flowering another set of plants in the other tent. Maintaining a balanced rotation like this can result in maximized harvests year over year.
Fluorescent lights are affordable and use minimal wattage to produce a low-intensity light. They are available in strips or larger arrays of multiple bulbs, and are most commonly used during the germination and propagation of seeds and clones. They should not be used during the flowering phase.
Indoor cultivation provides many benefits compared to outdoor cultivation, including control, reproducibility, and risk mitigation — not to mention location, location, location. The goal is to artificially create the ideal environment for your plants at all growth stages. This is achieved through precise lighting, temperature, humidity, carbon dioxide content, and air movement within each indoor growing space.
Even when growing cannabis legally, it’s a good idea to minimize your public visibility as a grower and take some mild to moderate precautions. Simple steps, such as not geotagging your location when you post grow pictures or hiding the glare from your grow lights when you run them at night, can go a long way in keeping your prized indoor garden secure.
Cleanliness in an indoor garden cannot be overstated. Clean your entire grow room before your first grow cycle and after every harvest. The walls, floors, trays, irrigation lines, reservoirs, lights, and fans should be cleaned using a three to five percent (3%-5%) hydrogen peroxide solution, an efficient sterilizing agent that leaves no dangerous or toxic residues behind. Be careful what you bring into your grow room. Pets, dirty clothes, and contaminated clones can introduce unwanted pests and diseases.