How to Identify the Sex Cannabis Plants

When we talk about growing cannabis for recreational or medicinal use, we predominantly focus on female plants’ growth. Cannabis is a dioecious species, which means that the plant’s reproductive organs occur on separate specimens resulting in distinctly male and female plants. Occasionally, male and female flowers occur on the same plant – known as hermaphrodites.  

Because of our focus on producing female flowers, identifying males from females and females from hermaphrodites is of utmost importance. If males or hermaphrodites grow alongside female plants, pollination will occur, causing females to create seeds.

Flowers, aka ‘buds’ with plenty of seeds, are not good to smoke. They taste bad, are very irritating on the throat, and are usually much lower in potency. This is because making seeds is energy-intensive, leaving less energy for producing trichomes.

Differentiating males from females is essential if using regular seeds, which have a 50% chance of being male or female.

Why is it essential to Identify Males and Hermaphrodites?

They both produce pollen, which will cause your female plants to produce hundreds and hundreds of seeds. Unless you are involved in breeding (for which carefully controlled males are necessary), you will need to remove male or hermaphrodite plants as soon as possible.

How do I Identify Male Cannabis?

It is really easy to identify the males but can be quite complicated when we talk about hermaphroditism, so let’s start with males and females.

Seed in a Feminised Plant Day 52

Cannabis plants often show their sex when they reach adulthood and are ready to flower. Normally this comes after the first month of vegetation (3 weeks on autoflowering).

For those who grow indoors and do so with short vegetative times of less than 1 month, it is feasible to see their sex from the first 3-5 days with the lights on 12/12.

To certify sex, you only have to look at the main stem nodes (it is always better to look at the highest nodes, as sex usually shows there first).

Male plants at first may look like a female’s sacks, but in a very short time, if not hours, you will see more and more sacks appear that turn into clusters of male flowers, which are like balls with a cluster of banana-like sacks inside, each of which contains large amounts of pollen.

It can be a matter of just a few days from the time they start appearing until the first ones start to open, which is why it is so important to quickly identify the males and shield your females from any source of pollen. It goes without saying that a good male must be saved if you want to crossbreed.

Day 21, Easily Identifiable Male

Identifying a Female Cannabis Plant

Female plants will show a small sac from which two V-shaped white hairs will emerge. These are called pistils.

Once you see this in your plants, you can relax – they are 100% female. Even so, we recommend checking your plants periodically, especially if they are suffering from some type of stress, as this can occasionally cause male flowers to appear, turning your female into a hermaphrodite.

Candy Cream Feminised Day 12

Pink Kush Auto Day 28

Identifying Hermaphrodite Cannabis

Hermaphrodite plants are those that show both sexes; there are two types – those that show both sexes from beginning to end and those that result from stress (most common stresses are heat, cold, high or low nutrition, extreme pruning).

The first group are easy to identify since they produce both sexes at the same time and usually do it from the start, which greatly facilitates the task of identifying and banishing. This is more complicated for the second group because these plants can produce very few or very many male flowers, depending on the stress level and the genetics’ susceptibility.

The problem, of course, is serious in those with a high incidence of male flowers but just as dangerous with a few, since it only takes a few of the banana-like sacks (flowers) to open, and there is enough pollen to pollinate a large portion of your female buds.

To this, we must add the difficulty of finding these sacks when the plant is already in advanced flowering since, normally, the individual banana-like flowers (the latter are usually shown in the middle of the buds, almost always hidden between pistils) are hidden by the leaves of the buds forming.

We cannot let our guard down for these types of plants, especially in plants with problems. The most recommended solution is to eliminate this type of plant as soon as you identify it to avoid any more trouble. Hermaphrodite pollen is not usually used for breeding since it is highly likely to maintain hermaphroditism in the offspring.

This should be all you need to know to grow your buds free of seeds. Happy growing!

If you need any further help, check out our Seedsman Community page.

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