Temperature: 68 to 78 degrees Fahrenheit. “A tool you should always have is a little temperature gauge,” Lipton said. “They call them hygrometers. They’re cheap and tell you both the temperature and the humidity.”
Though the 12-hour interval is fairly universal, knowing exactly when to induce flowering is less clear. For the home grower, it usually comes down to space; the longer one waits to trigger the flowering cycle, the taller their plant will be. A good rule of thumb: cannabis will only continue to grow 30 to 50 percent once the light source is reduced. If the plant is growing in a closet, growers should trigger the flowering cycle, understanding that there must be more than two feet of space between the canopy of the plant throughout the entirety of its life.
Find a healthy clone.
After 55 to 60 days, growers begin paying close attention to their plants’ trichomes — the small, bulbous fibers that develop around the flower of the female plant. “Those trichomes will turn from clear to amber,” Lipton said. “They kind of look like red hairs. You know it’s time to harvest when about 10 to 15 percent of the trichomes turn that color.” On average, cannabis plants have a five- to seven-day window of peak harvest time.
“Growing cannabis in tight spaces is not my usual recommendation,” said Stephen Lipton, the cultivation manager at The Farm Recreational Marijuana Dispensary, an award-winning recreational facility in Boulder, Colorado, specializing in what it calls “craft cannabis.” At any given time, Lipton oversees close to 15,000 plants across seven different facilities in Boulder County. “If you have a really tight space and it gets too hot or too humid, you’re going to have big trouble.”
Trigger the flowering cycle.
It’s important to remember that cultivating even one cannabis plant for personal consumption is felony on the federal level and punishable by up to five years in prison. Meanwhile, four US states — Alaska, Colorado, Washington D.C. and Oregon — have passed local amendments, allowing citizens who are 21 years old and over to grow a limited number of plants without fear of persecution.
But, with clones there’s a catch. Clones are cut off of a mother plant that is kept indoors under artificial light for 18 hours or more per day, so the mother plant and the little cutting “think” they’re living in an endless summer of long days and therefore remain in vegetative phase. If you put that rooted cutting outside in the spring under natural daylight, when the days are short, it thinks it’s fall and time to flower. A seedling, on the other hand, will wait till the light naturally fades again in the fall to go into flower.
The process of identifying which plants are male and which are female is known as “sexing”. It is an important part of cannabis cultivation that takes an experienced eye. At the nursery, we take the guesswork out of it and guarantee that our plants are all female.
The proper dryness is when the buds are dry, but not crispy to the touch. A good rule of thumb is to bend the stems below the flowers. If the stems snap but don’t break clean through, the flowers are probably about the right dryness. If the stems merely bend, let the cannabis dry some more. If the stems snap clean through into separate pieces, the flowers are probably too dry. If needed, they can be placed in a slightly more humid environment briefly to rehydrate so they don’t crumble when handled.
Detailed pest control is beyond the scope of this page, but you’ll need a small hand-pump sprayer and some organic pesticide. Any good grow shop can advise you. You don’t need to spend a ton of money to do basic preventative control. At the nursery, we use various organic pest control sprays preventatively about twice/week, but most home growers won’t need near that often of a spray schedule. If you are diligent with your microscope inspections, you may not need to do much at all if you don’t see any mites.
To harvest, cut the branches, remove all the large leaves by hand or with a scissors and hang the branches in a cool, dry place with plenty of airflow but minimal heat. There is an art to proper curing and it takes some experience to get it right. The main mistakes are drying too fast with too much heat, which causes the buds to crumble, and drying too slowly, which can cause mold. A cool, dry (not damp and moldy!) basement with a small fan blowing on a string full of branches is ideal unless you want to invest in specialized climate control equipment like commercial growers do.
While we can sell plants to you and you can legally drive them home, you may be subject to restrictions on how and where you grow them.
Cannabis has been the subject of such intensive breeding that there are virtually no “pure” sativa or indica strains. Virtually all are hybridized.