Male plants won’t show hairs at these nodes, but will develop little sacs of pollen. These pollen sacs will look like little balls. These balls can appear on their own or in clusters, depending how far into the pre-flowering stage the plant is. At some later stage of growth, the pollen sacs will burst open, spilling the pollen and possibly pollinating your females.
Obviously, no one wants to smoke seedy weed. When you grow cannabis and learn how to identify male plants and signs of pollination, you can remove these plants to save your remaining females. Likewise, recognising a pollinated female early allows you to start again before it’s too late, rather than finishing a grow that will only result in a poor-quality harvest.
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.
WHAT TO DO WHEN YOUR FEMALES GET POLLINATED?
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.
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.
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.
Anyone who starts out growing cannabis should know that there are two ways of going about planting: with seeds acquired from banks of cannabis genetics, like Dinafem; or from cuttings, that is, fragments removed from a mother plant for a reproductive purpose, to replicate its features.
One must remember that the male contributes about 25% of the plant’s final genetic material. Hence, until the crossing is carried out the grower will not know the final composition of his seeds. But what one always looks for, in order to get as many as possible, is a strong male with lots of flowers at the tip, and buds presenting dense pollen, as the prime objective is for a single male to be able to impregnate the greatest possible number of female plants.
Step 1: Identification of males and females
The development of the male’s flowers is progressive. First the flowers gradually turn yellow, changing from their original green colour. When the first male flowers begin to indicate that they are about to open, it is a good idea to turn off the fans in your grow room, while maintaining the air circulation, to keep the humidity from rising. Moving air can lead to the loss of pollen from the first flowers that open. About 10 days later most of the male plant flowers have yellowed, and then you’ll have to reduce your watering, without drying the plant, but without excess water either, as moisture helps flowers open faster.
In these parts, female plants develop “pre-flowers” that resemble a pear-shaped ball, from which grow two small hairs, usually white, commonly called pistils (though, actually, the pistil is the whole set of the stigma, calyx and ovary). They develop in a V shape, and in later stages group up, forming our precious buds. If you cannot locate them, don’t panic. This just means that your plant has not yet reached sexual maturity, so you’ll have to wait a few more weeks to determine its gender.
Females are ready to be pollinated after their early flowering stage, and when they have developed large heaps of flowers forming buds of a decent size. The best time to pollinate the female is when the flowers have fully-formed stigmas (the little white hairs), as long as possible, usually four or five weeks after the beginning of flowering, or 25 to 35 days, always depending on each strain. There are even strains that can be pollinated 20 days after flowering has begun.