The Cannabis Grow Bible
by Greg Green
Early sexing methods
First Early Sexing Method:
If you have been growing the same strain and all the seeds at the same time, then you may notice that some plants are taller than others. This is a sign that the smaller plants are female and the taller ones are male.
If you want too, you can separate your plants into two sections in order to see how good your guesswork was when you do finally identify sex. The other thing to know is that male plants in general start to pre-flower before females. If you have taller plants that are producing new growths before the smaller ones, then the taller plants are probably male.
Second Early Sexing Method.
A good way to identify plant sex at early date is to look at the calyx with the aid of a very fine magnifying glass.
If the calyx is raised on a stem then it is probably a male. If the calyx is not raised on a stem then it is probably a female.
Third Early Sexing Method.
Force-flowering a cutting is probably the best early sexing method out there. Simply take a cutting from the plant that you want to sex and place the cutting in a cup of water or into a cloning medium such as rockwool. Give the cutting 12 hours light and 12 hours total darkness. The cutting will flower and display its sex. Clones will carry the exact same genetic make-up as the plant it came from, including sex.
These methods are NOT 100% accurate but will help you to understand more about the visible differences between male and female plants. In a moment we will explain how to identify sex properly and completely.
THE PRE-FLOWERING TIME
Your plant will Pre-flower between 1 and 2 weeks and during this period the new growth regions begin to change shape depending on whether the plant is male or female. It is during this shape change that you can properly detect your plant’s sex.