There is a good reason why most growers keep male plants away from their ladies: Pollination from males causes the females to develop seeds. As a result, females focus their energy on seed production, rather than on growing you some fine-quality bud. This seedy and unfortunate final product can be avoided by implementing a few basic techniques.
Pollination of your female cannabis plants will make them produce seeds and spend less energy on producing quality buds. But when you recognise the signs of pollination early, you can avoid putting time and resources into a poor harvest.
A good test to see whether the bracts have swollen is to take a pair of tweezers, grab one bract, and open it up. If there is a seed inside, you have a pollinated plant.
Among the early signs that your female has been pollinated is that her bracts become larger. Bracts are small, leaf-like structures that protect the female’s reproductive parts. These are the sites from which the flowering buds appear. Do not confuse the bracts with calyxes.
The typical cannabis grower normally doesn’t have a reason to keep males, and will want to get rid of them as soon as they are spotted. Cannabis breeders, on the other hand, may want to keep males along with their crop of female plants. In such cases, the breeder will normally separate the sexes to avoid any accidental pollination. They may grow females in one tent and males in another. When grown outdoors, such as in a garden, the males are often kept in the most remote corner of their growing area, as far from the females as possible. Even then, because of the wind carrying around the pollen, there is always some risk of accidental pollination.
Another indication of pollination can be the colour of her pistil hairs. When a female has been pollinated, the previously white hairs will soon shrivel and become darker.
Spotting male cannabis plants and pollinated females early can save you from investing further time and effort into an entire growing season that will be for naught. Most of the time, the best course of action is to get rid of the males along with your pollinated ladies and just start a new grow.
Pollination requires the presence of males or intersex (hermaphrodite) plants, which are females that will also produce pollen. The first thing you want to do to keep the risk of pollination low is to remove as many males or “hermies” as as you can. Especially during the first three weeks of flowering, it’s important to frequently check for possible male specimens in your garden.
To determine the sex of your cannabis plants, you will have to wait until the pre-flowering stage when plants begin to put their energy into reproduction. Female cannabis plants show their gender signs later than males. At the location where they will soon grow their buds (the nodes between the stalk and the stem), females will show wispy white hairs.
Learn about the process of pollination and why you should avoid pollination of your female plants at all costs.