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.
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.
Female cannabis plants are the main focus of casual growers looking to harvest a personal stash. But, depending on their genetics, female plants can look drastically different from one another. Some remain small, producing dense canopies and significant lateral growth. Others grow in excess of 3m, produce massive harvests, and look more like trees than regular garden plants.
IDENTIFYING FEMALE CANNABIS PLANTS
Several factors can cause female plants to start to develop pollen sacs—or exposed stamens—alongside their flowers. This trait means that plants don’t need to rely on a nearby male to burst their sacs and fertilise them. As we’ll discuss in a bit, this is actually a savvy survival mechanism and a display of nature’s genius. However, hermaphrodites aren’t desirable in the grow room or garden. Now, let’s discuss both types and how to avoid the issues they cause.
Growers identify plant sex by identifying pre-flowers, which are small structures that form at the nodes during late vegetation.
Hermaphrodite cannabis plants come in two different forms: true hermaphrodites and “bananas”.
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.
But cannabis is an amazingly resilient plant and doesn’t require male pollination to produce seeds. Evolution has bestowed upon the cannabis plant an amazing ability to self-pollinate when there are no males around to do it for her. Whether stressed or old (for example, a female cannabis plant that is not harvested before her prime), if a female senses an environment that is not conducive to long-term growth, she will produce seeds in hopes that her legacy will continue.
Seed crops are harvested when the seeds are plump and dark, often with a tiger stripe appearance (around six to eight weeks into flowering). After harvesting, the bud is dried and the seeds are collected. Small-scale seed collection is done by simply crumbling the cannabis flower and collecting the seeds that fall out (this video by Johnnys Green Extractions offers a clever way to separate seeds from flower using an old vinyl record cover) while commercial seed collection usually involves special machines that crush dried flower then pass the trim and seeds into separate bins.
Natural Cannabis Seed Production
After seeds are collected, they’re stored in opaque, air-tight containers to prevent them from rotting or sprouting prematurely. Though cannabis flower is usually cultivated to be seedless, sometimes the seeds are the whole point. Breeders pay special attention to the pollination, harvest time, and drying process when growing cannabis specifically for the seeds to improve the likelihood of a successful harvest.
Have you ever harvested cannabis seeds? Share your experiences in the comments below!
The plants can “veg” here, or continue their vegetative growth phase, if trying to increase their size before seed production begins but it’s not necessary. Once the plants are large enough, they are put into a flowering light cycle of 12 hours light and 12 hours of complete darkness. Within a few weeks, the male will produce pollen sacks which will soon burst and get carried off into the air to pollinate the females. The females will now produce seeds which may continue to be used in the breeding process or harvested and sold to the public.