How to Tell the Sex of Marijuana Plants


Marijuana is a dioecious plant, meaning there are visible differences between male and female plants. So how to tell the sex of marijuana plants? Unsurprisingly, flowers are produced by female marijuana plants while pollen is produced by male marijuana plants, which will fertilize flowers. Like most other plants, pollen is released into the air or carried by pollinators to flowers and those flowers or buds will produce seeds.

Marijuana plants?

Female marijuana flowers, which people also call buds, contains the component tetrahydrocannabinol (THC) and cannabidiol (CBD). Male plants, on the other hand, cannot produce flowers, so there is an almost non-existent level of CBD in male plants and there is nothing to consume, so most of the time we want to get rid of them.

Most people grow marijuana plants for their flowers. They also want to separate the male plants and female plants, because seeded flowers are disgusting to smoke and consume, as well, seeds generally make flowers less potent since when flowers start producing seeds the plants have less energy to produce THC.

That all said, growers may still want male plants in their garden if they plant to reproduce their favorite plants. Since marijuana is a dioecious plant, its seeds inherit half of their genetics from their mother plant and another half from their father plant, making offspring crossbred plants, so growers can combine their two favorite plants together for something special.

Whether you’re a new grower or a mature grower, you will need to keep male plants out of your garden, so it is important to spot the difference between male and female marijuana plants. How to tell the sex of marijuana plants? First, we need to think about the stages of growth:

Stages Days (non-autoflower)
Germination 3 to 10 Days
Seedling 2 to 3 Weeks
Vegetative 3 to 16 Weeks
Flowering 8 to 11 Weeks

During the early stage of growth like germination or the seedling stage, you likely won’t be able to tell the difference between male and female plants. However, you should be able to tell the difference by a few weeks into the vegetative stage, and gender becomes obvious when it gets into the flowering stage—you don’t want to wait that long since the males will probably have already pollinated the females. Ideally, you would like to know the gender early in the vegetative stage.

Differences between male and female marijuana plants

Alright, so if you want to tell the difference between male and female marijuana plants, you need to keep a close eye on their reproductive parts as they mature. Here’s the key things to look for:

Female Plants:

  • They start growing these wispy white hairs called pistils at the points where the branches meet the main stalk. Those are the lady parts.
  • As the plant keeps growing, those pistils get all coated in these crystal-like trichomes – those sticky glands where all the good THC is made.
  • The female plants are the ones that produce those dank, resinous buds that everyone wants to smoke up for that high and medical effects.

Male Plants:

  • Instead of pistils, the males grow these little pollen sacs that look like tiny bunches of grapes.
  • When those sacs open up, they release a powdery pollen that can fertilize any nearby female plants.
  • Most growers ditch the male plants since they’re not packing much THC, and you don’t want them pollinating and seeding up your female buds.

It usually takes around 4 to 6 weeks into the flowering stage before you can definitively tell if a plant is a male or female based on those pre-flowers. Growers need to regularly check their crop and separate the males to get those prime, seedless buds from the unfertilized female plants.

How to Identify Female and Male Marijuana Plants?

Identifying female and male marijuana plants is crucial for successful cultivation. Female plants produce the cannabinoid-rich flowers sought after by growers, while male plants contribute pollen for seed production. To distinguish between the two:

1. Examination of Pre-flowers:

Pre-flowers typically appear during the vegetative stage, allowing early identification of plant sex. Female pre-flowers develop small, translucent hairs called pistils, while male pre-flowers form sac-like structures called pollen sacs.

2. Observation of Plant Growth:

Female plants tend to grow bushier with more branching to support flower production. Male plants often exhibit taller, slimmer growth patterns with fewer branches, focusing energy on pollen production.

3. Confirmation During Flowering:

As plants enter the flowering stage, the distinction becomes more apparent. Female plants develop dense clusters of flowers with pistils, while male plants produce elongated clusters of pollen sacs.

4. Preventing Pollination:

To avoid pollination and seed production, growers typically remove male plants once identified or use feminized seeds. Maintaining a consistent inspection routine throughout the growth cycle ensures timely removal of male plants, preventing undesired pollination and preserving flower quality.

All in all, by familiarizing oneself with these methods and regularly inspecting plants, growers can effectively identify and manage male and female marijuana plants, optimizing cultivation efforts and maximizing yields of high-quality flowers.

Marijuana Plant Gender in the Vegetative Stage (Sex of Marijuana Plants)

During the vegetative stage, a cannabis plant starts to grow its root and increase in size. Around week four to week six of growth, marijuana plants will start to grow pre-flowers. These flowers show that the plant is female. On the other hand, male plants will start to produce pollen sacs at this same time. So what is the difference?

Male pollen sacs are small green balls that are hard and round and dense. Female flowers are about the same size but have two white hairs—pistils—that sprout from the center of the sphere, and the spheres are not as hard or dense as the males. Females also have a pair of stigmas that collect the pollen spread by the males. We recommend using a magnifier or jeweler’s loupe to help you identify sex at this stage.

Marijuana plants

Marijuana Plant Gender in the Flowering Stage

When the marijuana plants enter the flowering stage the sex of marijuana plants will be easy to identify.

Male marijuana plants produce pollen sacs. When the sacs open, they will release pollen that looks like powdered sugar. Female marijuana flowers look different than other flowers. Contrary to most of the flowers we see in gardens, marijuana flowers have a core made of tiny leaves; they’re not soft nor do they have open petals. These thin leaves look like sugar crystals, they are called sugar leaves.

Identifying Hermaphrodite Cannabis Plants

Marijuana plants can sometimes be hermaphrodites. Hermaphrodite marijuana plants produce both male pollen sacs and female flowers. Occasionally, hermaphroditic plants appear because of genetics, but most of the time, it is because the plant is under some type of stress: root rot, excess heat, and malnutrition can lead to marijuana hermaphroditism.

There are two kinds of hermaphroditic marijuana plants: true hermaphrodite and mixed gender. A true hermaphrodite plant has male and female sex organs but in different areas of the plant. Mixed-gender marijuana plants have yellow sex organs called anthers, and these are usually grown by females that will still produce pollen and will pollinate nearby flowers.

Regardless of the type of hermaphrodite cannabis plant you find in your grow room, it is best to remove it and treat it like a male plant rather than a female plant since it still can pollinate your other females. And if you decide to breed a hermaphroditic plant with a female plant you have a good chance of getting more hermaphroditic plants in the future.

Hermaphrodite Pot Plants

Hermaphrodite marijuana plants can sometimes occur, where the plant exhibits both male and female reproductive organs. This is generally considered undesirable for most growers. Here are some key points about hermaphrodite (hermie) cannabis plants:

  • They develop both pollen sacs (male) and pistillate flowers (female) on the same plant.
  • It can be caused by environmental stressors like high heat, drought, light disruptions during the dark cycle, or genetic factors.
  • If pollen from the male organs gets transferred to the female flowers, it can cause seeded, lower-quality buds.
  • The seeds will be fertilized and will not maintain the original strain’s genetics if planted.
  • Hermies increase risk of accidental pollination for nearby female plants in a grow operation.
  • Growers typically remove any hermaphrodite plants from their crop immediately to prevent unwanted pollination.

Identifying hermies can be tricky as the male pollen sacs can be small and hidden within flower clusters. Closely inspecting all flowering sites is necessary to catch any hermaphroditism early before pollination occurs. Overall, most growers aim to prevent hermie expression and grow pure, unfertilized female plants.

To Sum Up

So we’ve broken down how to tell the sex of marijuana plants, so examine your plants carefully and make sure you’re growing just what you want.

If you have any questions, please don’t hesitate to reach out to us!

And be sure to check out our other blog posts for useful tips on becoming a great grower!

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