Tips on how to grow your own marijuana

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When it comes to growing his own marijuana, Chris Haynie leaves little to chance.

Inside a grow room in Richmond, Haynie has erected a 42-square-foot tent that houses four marijuana plants, the state’s legal limit for personal cultivation. Haynie’s setup is high-tech: An irrigation system releases moisture on a precise schedule; a motorized LED light timed to mimic the rising and setting of the sun moves along a rail across the top of the tent; and a monitoring system tracks key metrics of plant health, such as the moisture level and pH of the soil, and relays the data to an app on Haynie’s phone. If the system senses urgent problems, he’ll receive a warning text. Haynie’s friends are used to him bolting from a room mid-conversation to tend to his plants.

Haynie, the bearded 38-year-old cannabis connoisseur who tattooed his thumbs with green ink, is no horticulture amateur. As the co-founder of Richmond’s Happy Trees Agricultural Supply, he’s part of a growing number of experts who are making a business out of teaching people how to grow their own pot. Recent laws in Virginia allow for limited cultivation of marijuana for personal use, and Happy Trees, which Haynie launched in 2019 with Josiah Ickes, 36, specializes in setting up growers to cultivate the plant.

Marijuana remains illegal on a federal level, but many states have abolished restrictions, creating a patchwork of rules throughout the country. Eighteen states and the District of Columbia have passed laws allowing recreational use. Virginia legalized home cultivation in July 2021; under the law, people 21 and older may possess up to an ounce of marijuana. It remains illegal, though, to buy or sell it in any form — including seeds — until 2024, when retail sales are expected to begin.

People still find ways to access seeds. When DC legalized the possession of limited amounts of marijuana in 2015, the District lacked the authority to create a legal economic market for sales. So cannabis activists organized seed giveaways throughout the city. At one early event in 2015, lines stretched for blocks.

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The regulatory scheme also established what has become an expansive “giveaway market,” in which Washingtonians have used a loophole to provide harvested marijuana as a gift in exchange for the purchase of a legal product. Companies sell cookies, tea or paintings with a baggie of “free” marijuana on the side. One company sells motivational speeches delivered by a person who travels by bicycle.

Virginia’s 2021 law, however, included language that avoided DC’s loophole, effectively banning the creation of a gift market in the state. Virginians are allowed to gift seeds, but companies cannot gift marijuana along with the purchase of another product.

The limited legalization has helped launch companies eager to teach people how to grow marijuana. Happy Trees runs growing workshops. And companies such as Green Flower, which has partnerships with some universities, offer cannabis certificate programs that include cultivation training.

“Growing cannabis is not hard,” Ickes said. “But when it comes to growing quality cannabis that has certain profiles that people are looking for, that can be exceptionally challenging.” Here are some suggestions from experts on how to grow your own.

Although new growers won’t need all the gadgetry that Haynie uses, there are a few essential items beginners should consider.

First, you’ll need some information about the plant you’re growing and your cultivation approach. Do you plan on growing indoors or out? In soil or using a hydroponic system? Are your plants auto-flowering, meaning they don’t need simulated intervals of light and darkness, or are they photoperiod plants, which do?

Growing indoors will require a basic setup: a container with soil and fertilizer, and a lamp for the grow tent. But not just any light will do.

“You need a way to replace the sun,” Haynie said. “Your average fluorescent light bulb is not the right color spectrum for cannabis. It’s a very common problem. You need lights calibrated to specific light spectrums.”

Haynie recommends lights designed specifically for growing marijuana, which change depending on the plant’s growth stage. Blue spectrum lights are best during the plant’s seedling and vegetative stages, while red spectrum lights are ideal during flowering. Local grow shops can help you find the right kind of light for your situation.

Beginners usually start with a 4-by-4-foot grow tent that blocks external light, a fan to simulate wind and a humidifier to regulate moisture. An exhaust system will help remove heat from the tent, and you should have tools that measure temperature, pH balance and moisture.

A basic setup can cost about $250 to $1,400. More advanced systems, such as Haynie’s, can cost thousands more. The total life cycle from seed to harvest for a photoperiod cannabis plant could be as long as 160 to 180 days, he said.

A marijuana seed can germinate in as little as 24 hours and should be planted in a warm, humid environment. A typical beginner plant in a small container spends four to six weeks in its vegetative growth stage, but larger plants can take longer.

“You’ll want to see vibrant colors, a healthy growth rate, no wilting or drooping,” Haynie said. “Healthy plants have a very distinct look.”

After watering the plant, wait until it dries out before reapplying direct moisture to help build the root mass in the container.

Look for pests or signs of debris, which could choke the plant. Spider mites, aphids or thrips are common. Watch for signs of fungal and bacterial diseases, such as powdery mildew, bud rot, mold or bacteria, which you’ll be able to see growing on the plant in the same way mold appears on food. Keep the area clean by removing any leaf debris that has fallen into the pot.

The plant’s scent will increase as it gets closer to flowering. Breeders have grown plants to emit various smells, including of coffee, peas, cake batter or, as Haynie described his personal favorite, “a skunk covered in kerosene.”

The flowering stage can last about eight to 10 weeks. When the plant begins to flower, the light cycle changes, so the plant gets 10 to 12 hours of uninterrupted darkness per night.

You’ll know it’s nearing time to harvest when you see color changes on the trichome gland heads (the sticky part of the plant that contains THC). Watch to see whether the pistils begin to turn red and the leaves begin to change colors. Use an optical magnifier to inspect the buds in search of the resin-coated trichomes.

Even when it’s ready to harvest, you’ll still have to wait a bit longer before consumption. Patience and careful monitoring at this stage is crucial.

“Some of the best herbs I’ve ever grown got completely ruined when there was a malfunction with a dehumidifier in the grow room that dried out in three days,” Haynie said. “I’ve also lost other cannabis to mold, because it dried too slowly.”

Once harvested, let it cure for about three weeks. The curing process allows the desirable smells and flavors to come out of the plant.

Chris Moody is also a freelance writer in Chattanooga, Tenn.