When to Separate Male and Female Cannabis Plants


Turn your problems into wisdom
May 22, 2018 by Kevin Klein

When to Separate Male and Female Marijuana Plants

When to Separate Male and Female Cannabis Plants

For the home grower, the practice of culling male plants is extremely important to the overall success of the cultivation project. Today’s home growers typically acquire their seeds from a seed company or bank and have a choice between feminized seed (seed that will produce only female plants) and normal seed (seed that will produce both female and male plants).

Growing From Feminized Cannabis Seed
If growing only female plants is the ultimate goal, there’s much to be said for the merits of feminized seed. This type of seed comes from specialized breeding practices that only utilize female plants, so this seed lacks the male chromosomes to produce male plants. When the plants begin to reveal their sex, they will all be female.

Growing From Normal Cannabis Seed
Growing plants from normal seed requires more work, close observation, and a keen eye. When starting a garden from normal seed, the grower will begin in an identical manner as with feminized seed. Most people will follow standard guidelines for the vegetative and flower stages of the cannabis life cycle, utilizing 18 hours of light to six hours of darkness each day for the vegetative stage.

Getting Through the Vegetative Phase
The use of timers is mandatory to properly grow cannabis indoors (be sure to use timers that are compatible with the wattage of the lights used). This 18:6 vegetative light cycle mimics the average length of the long days of spring and early summer, when plants grow at a fast rate. During this phase, cannabis plants grow vertically and gain height quickly. After approximately one month of growing, the plants will be roughly 1 to 1½ feet in height, depending on the strain.

Some cultivators grow their plants to shorter or taller heights during the vegetative phase before putting them into the flowering phase, depending on personal preference.

Moving Into The Flowering Phase
To induce flowering, the timers are scaled back to an even 12 hours of light to 12 hours of darkness. This 12:12 flowering light cycle mimics the shortening days of late summer and early fall, when many plants or trees bloom and bear fruit or flowers.

While the shortening days happen very gradually outdoors, the plants will detect the shorter light phase quite quickly indoors, sometimes as quickly as a few days. Usually within three to 10 days, the plants will reveal their sex. This is a critical stage for the grower.

Until all of the plants show the telltale signs of being either male or female, the grower must evaluate them once or twice per day. When using normal seed for a grow, the ratio of males to females will be fairly even or produce slightly more females than males.

Determining The Sex Of Your Cannabis Plants
Is your plant male or female? Males will typically reveal their sex sooner than females. The grower must keep an eye on the juncture where individual lateral branches meet the plant’s main vertical stalk. Male preflowers appear as staminate primordia that appear to be small clusters of balls.

Female preflowers appear in the same area of the plant as males preflowers and appear as calyxes (pistil primordia) and pistils that appear to be small white hairs. Male preflowers can mature quickly and produce pollen in a surprisingly short amount of time.

Separating Male & Female Cannabis Plants
The grower must ensure that all male plants are removed from the female grow room before the release of any pollen. Not doing so spells complete disaster for the success of the grow and production of high-quality, seedless flowers.

The best advice for novices is to remove male plants immediately upon identification and destroy them by cutting them down and discarding them in plastic bags that prevent any leakage of pollen.

The importance of separating male plants from valuable females cannot be emphasized enough. Failing to remove males soon enough will render the grow useless for the production of high-quality flowers. A little pollen can go a very long way and completely seed all females in the room. Heed this warning!