By Brian Barth

The federal government still considers it a crime to grow or possess cannabis, but 30 states have now legalized it to varying degrees. Washington, Oregon, California, Alaska, Nevada, Colorado, Maine and Massachusetts have decriminalized weed for recreational use, and similar legislation is under consideration elsewhere. Pardon the pun, but it is high time we talk about how to grow the stuff.

The old-fashioned way—outdoors—is easiest. The trend towards indoor cultivation is more a product of, one, a desire to hide what you're doing (no longer necessary in many locales); and two, to exert total control over growing conditions for the sake of producing enormous buds with maximum market value. But if your sole goal is just to have a bit of decent weed around to occasionally enjoy, you may as well plant it alongside your zucchini and basil.

Growing a successful cannabis crop is a bit more complicated than your average vegetable, but not much. Before you get carried away, familiarize yourself with your local laws—NORML provides a comprehensive list here. Horticulturally speaking, here's what you need to know.

Varieties

Plenty of mail-order firms have sprung up to fill the demand for legal plant material. There are thousands of varieties, with all the trippy descriptions you would expect. If you want a cerebral high and non-skunky citrus flavor, there is a breed for that; if you want something that is good for anxiety, low in THC, and grows less than 3 feet tall, you can find that too.

Most importantly, purchase seeds for varieties suited to outdoor conditions, rather than those bred for indoor grow operations. Any reputable supplier will specify that information in their varietal listings. Most will also note mold-resistant varieties, which are a wise choice in humid regions, as well as those with a "short flowering period," an important consideration in northerly latitudes (this is akin to the "days to maturity" listed on packets of vegetable seed).

Understanding Male and Female Plants

Cannabis is one of many species in the plant kingdom that produce male and female flowers on separate plants. Females produce fat flower "buds" rich in psychoactive compounds, while male plants produce spindly little flowers that aren't worth smoking (or however you choose to partake).

When you plant cannabis seeds, you typically end up with about half male plants and half female plants. It is imperative to get rid of the males before the plants begin to flower, as the male pollen will result in female buds that are full of seeds, which is no good. It's not that hard to determine the sex of cannabis seedlings—you can find instructions here—and cull the males.

But it can be even easier! How? Look for varieties labeled "feminized." These are seeds that have been bred to produce only female plants and are highly recommended for novice cannabis gardeners.

Another option is to purchase "clones," which are rooted cuttings of female plants. This is essentially like buying vegetable seedlings, rather than seeds, which saves you the time and effort required for germination, along with the trouble of weeding out the males.

Starting Seeds

Weed seeds require no special treatment, though they'll germinate faster if you soak them in water for a few days before planting. As with tomatoes and other heat-loving vegetables, you're better off starting the seed indoors in a sunny window in early spring, and then transplanting the seedlings outdoors once all danger of frost has passed.

Growing Conditions

To do well, cannabis plants require a minimum of six hours of direct sun each day and excellent drainage. They'll do fine in a typical raised bed like you'd use for vegetables, though five-gallon pots filled with potting soil also work well for pot (hard to resist the punny wordplay!). Good air circulation is critical for preventing fungal diseases, so space the plants at least six feet apart (closer is ok for dwarf varieties) to ensure that they don't resemble a dense hedge by the end of summer.

Cannabis plants love their nutrients, so plan to enrich the beds with composted manure, ideally at least one month prior to planting, if not the previous fall. Spread a minimum of 2 inches of compost over the planting area and work it into the soil. If planting in pots, you can rely on fertilizer, rather than compost.

Feeding and Watering

This crop is also a thirsty one, so be sure to irrigate whenever the surface of the soil becomes dry. Adding a layer of mulch once the plants are knee-high will cut back on the loss of soil moisture through evaporation and help to prevent other "weeds" from getting established in your weed planting.

If your beds are sufficiently rich, fertilizer is not required, though it will lead to better results (it's a must for potted plants). Apply a high-nitrogen fertilizer every three weeks until mid-summer, as this will stimulate abundant vegetative growth. Then switch to one higher in phosphorus to stimulate dense and abundant flowers (buds).

Pruning

Depending on the variety, outdoor plants can grow 12 feet or more in height. Most growers prune them, which makes the plants easier to manage and results in far more buds. Professional growers have perfected pruning to a fine art for the sake of maximizing yield, but for the casual grower is sufficient to cut back the most vigorous shoots from time to time. Simply clip off the outer 30 percent of each major shoot every few weeks.

Pruning encourages a bushier form (rather than a tall, spindly plant) by stimulating the growth of numerous small side shoots, each of which will produce additional buds. Just be sure to stop pruning by mid-summer, so as not to interfere with flower production.

Harvest

Buds will begin to form in late summer and should be ready for harvest during the month of October. You'll know they are ready when the flower pistils—those wispy hairs that emanate from the buds—turn from white to reddish-brown.

Cut the buds from the plants, leaving 6 or 8 inches of stem below each one, and trim off all the leaves. Hang them from their stems to dry in a warm, shaded place for about a week. The weed is now ready to use. Trim the buds from the stem and store in a glass jar.

Reposted with permission from our media associate Modern Farmer.