Male vs. Female Cannabis: How to Determine the Sex of Your Plant
Cannabis plants show their sex by what grows in between their nodes (where leaves and branches extend from the stalk). What starts as a pollen sac on a male plant or a stigma on a female will become what either spreads or catches pollen, respectively. Luckily, we can see these differences weeks before they actually start serving their purposes in the reproduction cycle. These are known as “pre-flowers.”
Pre-flowers begin to develop four weeks into growth, but they may take a little longer depending on how quickly the sprouting phase occurred. By the sixth week, you should be able to find the pre-flowers and confidently determine the sex of your plant.
Pre-flowers can initially be extremely small and hard to identify with the naked eye, but you can use a small jeweler’s magnifying glass to get a better look. Examine the nodes of the plant and look for either the early growth of small sacs (male) or two bracts (female), which will eventually produce the hair-like stigma.
Though there are other methods to determine what sex the plant is, examining pre-flower formation is the most reliable. Removing males early on is important for two reasons: it frees up space in your garden so females grow bigger and stronger, and it prevents males from pollinating females.