female Cannabis Plant male
Clusters of flowers known as buds or colas only occur on female, or hermaphrodite plants. Hermaphrodites are plants that are part male part female. If you want sinsemilla buds make sure you only have pure females.
Plants in constant light can sometimes start to show some pre flowers after only a few weeks of growth. Usually though it takes a change in light cycle to trigger the plants into full reproductive mode.
Unless you have plans to breed or to produce lots of seeds always separate male and female plants as soon as their sex becomes apparent. Remember one or two male plants can turn a whole crop to seed.
Early female flowers look like little furry hairs, usually white, but they can be other colors. Early male flowers look a bit like small bunches of mini green bananas. Look near the leaf joins on your plants to see them emerging.
Most varieties of cannabis require 12 hours of darkness per day to induce their flowering cycles. Sativa varieties sometimes need more. Indica varieties can sometimes take less. Ruderalis varieties can flower whatever.
Even pure female plants have the potential to turn male or hermaphrodite. This can happen if the plant is stressed to much through bad treatment or if chemicals are applied to the plant to induce male flowering.
Once you have a good female plant that you would like to keep you can place it in constant light to stop it from flowering. This plant can then be a “mother” for you to take cuttings from whenever you wish.