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.
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.
HOW TO AVOID POLLINATION OF YOUR FEMALE PLANTS
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.
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.
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.
These protruding structures are designed to capture pollen, which leads to fertilisation. They stick out away from the flower to capture pollen from the air, and to await being brushed up against by pollen-covered insects.
Male plants, in contrast, don’t produce flowers. This makes them less valuable for growers seeking only buds. However, they do produce pollen sacs. These small vessels create the genetic material required to fertilise female flowers and create hybrids. This makes the males extremely important for breeding new cannabis strains.
A guide to differentiating between male, female, and hermaphrodite cannabis plants.
IDENTIFYING HERMAPHRODITE CANNABIS PLANTS
Growers identify plant sex by identifying pre-flowers, which are small structures that form at the nodes during late vegetation.
Hermaphroditism stems from two major driving factors: stress and genetics. In regards to stress, hermaphroditism serves as a survival mechanism. If a plant experiences damage, heat, disease, or nutrient deficiencies, they start to freak out. Essentially, plants get the impression that their time is up. In a last-ditch attempt to reproduce, they decide to stop waiting around for a male and get the job done themselves.
Male and female plants look identical during the seedling and vegetative phases. But, as they begin to transition into the flowering phase, plants finally begin to reveal their sex. During this time, females produce resinous buds loaded with cannabinoids, and males form sacs filled with pollen.
During the early flowering stage, take a stroll around your grow room or garden with a magnifying glass or jeweller’s loupe. Inspect a few nodes on each plant to see how far along into the flowering process they are. At this stage, you won’t see any obvious flowers or pollen sacs. Instead, you’re looking for young pre-flowers. Although these tiny structures look similar, they have distinct features that allow growers to tell them apart.