Bract
A bract is a small, specialised leaf-like structure that protect the area where new seeds are produced on cannabis plants.
In Cannabis sativa L. plants, the bracts are an integral part of the anatomy as they hold the ovule (which produce new seeds when pollinated). The bracts are 'tear-drop' shaped, and wrap around the ovule to protect the emerging seed. Bracts are covered in trichomes, which is where the therapeutically active cannabinoids and terpenes are mainly produced.
What is the difference between a bract and a calyx?
In cannabis plant anatomy, the bracts are situated inside the calyx, which is the first part of the flower to develop. The calyx acts almost like a protective cover during the budding phase, whereas the bracts actually house the plant's reproductive organs, including the pistil.
Why are bracts important to growers?
Given that bracts play a vital role in the reproductive cycle of cannabis plants, it is important for cannabis cultivators to understand how to look after them, and how to ‘read’ them. Bracts enclose the female’s ovule, and after pollination, a seed develops inside. When the plant is ready to be harvested, the bracts often become swollen and resinous, especially when containing a seed.
Do all female cannabis plants produce seeds?
No, only female plants that have been pollinated by a male will produce seeds. Seed production is actually mostly seen as a negative when cultivating cannabis for cannabinoid and terpene production, as it diverts energy away from developing buds and can lead to lower levels of trichomes, where the therapeutic compounds are formed.
In modern cannabis cultivation, female plants are usually only exposed to male pollen in the breeding process, when new cultivars are being created.
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