Marijuana flowers come from female plants. Male plants do not produce usable marijuana flower, but instead they create pollen sacs which will pollinate female buds to create seeds. For this reason, growers remove male plants from the garden to avoid harvesting female buds with seeds. Distinguishing male plants from female at the earliest possible time is important for growing female flowers without seeds.
Telling the difference between male and female plants is fairly simple if you know what you are looking for. Timing is important, as you want to remove males at the earliest point of identification to avoid seeding your females. There is also the issue of hermaphroditic plants - a female plant that displays male flowers and releases pollen. These should also be isolated from female plants, and discarded.
With a trained eye it is sometimes possible to determine the sex of a plant during the vegetative growth cycle by observing preflowers. Females are usually easier to spot because most strains will show preflowers after they have grown past four or five nodes. Spotting the fine white pistils may be difficult at first but once you see them, you know the plant is a female.
Determining a male during vegetative growth is not as easy. Seeing a pair of pollen sacs is a sure sign that the plant is a male (or hemaphrodite), but this often this requires a trip to the flowering room and a watchful eye. Not all strains will show in during vegetative growth, and not all growers will be able to catch things there the first time through. Examine the picture above, take your time and be conservative before making the call on a plant. Cannabis gardeners are understandably paranoid and scared of males because even a single male in a flowering room with good air circulation will pollinate every female in the room. Knowledge is power here. Learn how to sex your plants accurately and be confident when you make these decisions. A second opinion never hurts when you lack the experience - schedule a free 15 minute consultation via video chat if you need our help.