Sexing cannabis plants is vital for maximising your harvest. In this article, you’ll learn how to sex your marijuana plants (even before they flower), when flowering occurs, and how to induce flowering.
Cannabis begins to flower when it receives 12 hours of light and 12 hours of uninterrupted darkness in each 24-hour cycle.
Once this light cycle (or photoperiod) is initiated, plants enter the pre-flowering stage, when they increase in size as the branch structure prepares to bear and support flowers.
How to tell if your plant is male or female before flowering?
During pre-flowering, which usually lasts about 10 days, it is still not possible to identify the sex of the plant. The first flowers should be visible within two weeks.
Female cannabis plant
Male cannabis plant
Using feminized seeds or automatic seeds should eliminate this process as they are bred to produce plants that will flower as females.
Inducing flowering for sexing marijuana plants
Indoors, it is the grower who decides when to alter the photo period and induce flowering. This is achieved by simply adjusting the timers on the lights.
Outdoors, the grower must wait until the natural daylight hours have decreased to approximately 12 per day. Exactly when this occurs will of course vary depending on the locality. In Northern Europe it happens around mid-to-late July.
It is possible to induce flowering outside by allowing the plants 12 hours of daylight each day, then covering them or taking them inside.
This must however be done every day without fail. If the periods of darkness are interrupted by light, this can adversely affect the plants, setting it back to a vegetative state.
Disclaimer:Laws and regulations regarding cannabis cultivation differ from country to country. Sensi Seeds therefore strongly advises you to check your local laws and regulations. Do not act in conflict with the law.