Can You Tell The Sex Of Cannabis Seeds?

If you are a veteran of the cannabis community, or spent a lot of your time reading up on cannabis, you may have heard that it is possible to tell the sex of cannabis seed simply from its appearance. There is even a chart floating about out there that describes the physical differences between male and female seeds.

Well, let us tell you now, it is all a load of bollocks. There is no way to tell the difference between male and female cannabis seeds by looking at them. In fact, it is widely accepted that the sex of a cannabis plant is not determined until a few weeks before flowering.

Even feminized seed, which have been bred to have 99.9% chance of growing female, can turn into male or hermaphrodite plants if put under a ton of stress while growing. This is very rarely a worry for feminized growers, as they don’t tend to stress out their plants to this extreme extent – but it is possible.

Think about it. Why would breeders across the globe go to all the effort required to produce feminized cannabis seeds if they could simply look at regular cannabis seeds and categorize them? It isn’t some conspiracy or well-kept trade secret.

DETERMINING THE SEX OF YOUR CANNABIS BEFORE IT COMES A PROBLEM

While being able to determine the sex of a cannabis seed by looking at it is a myth, being able to sex your cannabis early isn’t.

Normally, you would wait until your cannabis plants are done with vegetative growth, and switch them over to flowering. You then watch like a hawk for any signs of sex, and move the males as soon as possible. This is risky, though, because if you leave it too long, you risk the chance of pollination – turning your bud into seeds. Unless you are getting into breeding yourself, this is something you probably want to avoid.

If you don’t want to take the risk, then sexing your cannabis early is pretty easy, and stress-free. It basically involves placing a black bag over a small section of the plant during the vegetative stage to force pre-flowering, before allowing it to revert back. This gives you a clear idea of what sex your plants are, without undue worry, wasted time, or effort.

It is a sad truth that you cannot determine the sex of a seed by looking at it. If you think you can, you have been lucky. Nothing more. However, hopefully, our explanation of the measures you can take to determine the sex of your cannabis plants will help you keep your grow room male free for years to come!

Luke Sumpter

With a BSc (Hons) degree in Clinical Health Sciences and a passion for growing plants, Luke Sumpter has worked as a professional journalist and writer at the intersection of cannabis and science for the past 7 years.

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