The stunning results of this week’s vote include a significant change for gardeners:
removal of a long-standing ban on growing cannabis for personal recreational use by adults.
Voters approved Proposition 64, which legalizes “growing up to six marijuana plants and keeping the marijuana produced by the plants within a private home.” This column provides a brief introduction to the cultivation of marijuana; interested gardeners should read all of the proposition’s provisions related to personal uses of marijuana.
Cannabis (Marijuana), a herb with psychoactive properties, is a genus of the Cannabaceae family. Other genera in this family include Celtis (Hackberry), Humulus (Hop) and about eight other less familiar plants.
There are three species of Cannabis: C. sativa, C. indica, and C. ruderalis. There are many C. sativa x indica hybrids that combine sativa’s productivity and indica’s more compact size.
The plant grew originally in mountainous regions northwest of the Himalayas, and is now indigenous to central Asia and India; it grows well in much of California.
Cannabis is dioecious, meaning the genus has separate female and male plants. Only about 6% of flowering plants are dioecious; the great majority is monoecious, having both male and female flowers.
The flowers of well-grown female plants (called sensimilla, meaning “without seeds”) of both C. sativa and C. indica secrete an abundance of chemical compounds (cannabinoids), mostly tetrahydrocannabinol (THC), a psychoactive constituent, and cannabidiol (CBD), which has a range of medical applications.
Growing cannabis for personal use would be well within the skills of typical gardeners: the plant grows so vigorously that it is commonly called “weed.” The reasons for growing your own marijuana include controlling expenses, avoiding synthetic chemicals, and selecting preferred cultivars (“strains”). Growing the plant for optimal production of THC involves some care, so the challenge to succeed could be satisfying in itself.
Local garden centers are unlikely to offer Cannabis seeds or seedlings in the near future. Two local garden center managers told me they would stay out of the Cannabis market at least until federal laws allow personal, recreational use of the plant.
For this reason, the best way to begin is to buy seeds online. A search of the Internet for “Cannabis seeds” will yield links to several vendors offering various strains, each with features of potency, productivity, fragrance, taste, disease resistance, etc. Generally, seeds are offered online in small packets, with prices ranging around $5 to $10 per seed. Growers claim germination rates of 90-95%, so two or more gardeners might share the cost of a seed purchase.
Cultivation of the Cannabis plant proceeds through stages:
- Sprouting Stage. Germinate seeds in the spring by placing them in a damp paper towel. The seeds should show a small white taproot within 72 hours. Plant the seeds ¼-inch deep in planting mix with the root pointing down in a small biodegradable container, e.g., a peat pot. Keep the soil slightly damp with de-chlorinated water (leave tap water in an open container for 24 hours to release chlorine gas). Leave for 1 to 3 weeks.
- Vegetative Growth Stage. Move the small plant (still in its biodegradable container) to a 3-to-5 gallon pot filled with planting mix plus compost. The mix should be kept slightly damp with slightly acidic (low pH) water, and the plant should receive maximum sunlight. If growing indoors, maintain 72–85°F, and provide a high level of light for 18–24 hours/day. Feed the plant with high-nitrogen fertilizer. During this stage, prune off about ¾ of the top growth tip to promote new top growth and additional buds. This is also the right stage to take cuttings for the propagation of clones.
- Flowering Stage. Once the plant grows to18 inches or more in height, it will be ready for flowering. To stimulate flowering, provide strong light for 12 hours/day, and complete darkness for 12 hours/day. If the plants have been growing outdoors, this could require moving the plants indoors for the dark period each day. During this stage, the plants could double in size.
- Harvesting Stage. Reaching this stage could take 5 weeks, during which the plant benefits from phosphorus (e.g., chicken or bat compost tea) more than nitrogen. As the buds develop, they will emit resinous trichomes that will change from clear to cloudy to amber in color. Using a low-power magnifier, watch for when about 50% of the trichomes become amber, indicating that the buds are ready for harvest. Cut each of the bud masses, keeping them large and intact.
- Drying and Curing Stage. Air-drying is simplest and most popular. Suspend the bud cuttings upside down in a room with moving air for about seven days. Then, place them in airtight glass jars for at least 2 weeks. Longer is better. To release moisture, open the jars daily to during the 1st week, and every other day during the 2nd The marijuana should then be ready to smoke.
There is much to learn. Several “how-to” articles and short books are freely available online, revealing perhaps what generous marijuana cultivators do while their plants grow. To find and download these resources, search the Internet for “how to grow marijuana,” or visit selected websites listred below.
Growing your own marijuana is like making your own wine: it’s possible but not for every gardener. Let us know of your experience!
I Love Growing Marijuana — An experienced cultivator of marijuana, Robert Bergman, maintains this website which offers many free or low-cost resources for cultivating Cannabis. The site also offers a variety of Cannabis seeds, with brief descriptions of their properties.
Seed Supreme — Another source of Cannabis seeds.