How to distinguish males from females in cannabis growing
Marijuana (cannabis sativa sp.) is a dioecious or unisexual plant, what means that it produces male and female flowers in different individuals, although we can find both types of flowers in hermaphrodite plants. We call males those plants that produce male flowers, and females those producing female flowers.
Marijuana males flower producing small bell-shaped clusters, that hang down and open releasing the pollen, while females produce tear-shaped calyxes with two pistils – usually white – that group together forming what we call buds.
When to determine the sex of marijuana plants?
Generally, cannabis plants start flowering when nights – dark periods – are longer, which is a sign to show their sex and start blooming. Actually, marijuana plants reach their sexual maturity between 6-8 weeks after seed germination , regardless of the photoperiod.
It is this fact what can help us to determine the sex of our marijuana plants without the need to make cuttings or change the photoperiod, what could strees our young plants.
As we mentioned before, when plants are about 2 months old – when they have 5 or 6 internodes – they are sexually mature, which is to say, they have set their sex. In some cases – most of them produced by stress – plants will show both sexes, being what we call hermaphrodites, but generally at this moment plants show their true sex, that will mantain for their entire life cycle.
This technique of premature detection of the sex needs a little practice, but once mastered it will allow us to determine the sex of our cannabis plants at a very early stage.
Sexing marijuana from cuttings
If we can’t sex our plants with this technique, we can take a cutting from each of our marijuana plants and flower it in a growing tent – 12 hours of light/darkness photoperiod – what will force it to flower and show its sex, that will be exactly the same as its mother plant.
What we don’t recommend at all is forcing the flowernig of mother plants for a few days/weeks and once they show their sex placing them again with a growing photoperiod (18 hours of light/6 hours of darkness), since this will produce major hormonal changes inside the plants, being an easy way to stress them – what will improve the chances to get hermaphrodite plants.