How Do You Identify and Care for Male vs Female Marijuana Plants?

The cannabis plant is one of the heartiest and easiest plants to grow, and it can be found growing wild in every state in the union. Even though it grows naturally, there’s still careful attention paid to each cannabis plant when it’s cultivated, either for resin-filled flower, or CBD rich seeds.

Generally, only cannabis breeders and hemp farmers are interested in growing marijuana with seeded buds, which requires a female marijuana plant to be fertilized by male marijuana plant's pollen.  Anyone growing cannabis strains for THC content will want to pick out any male marijuana plants, so that the flowers on the female plants grow large and seedless.

If stopping by your nearest dispensary has become too easy for you, here’s a handy guide to help you determine a cannabis plant's sex. If you want to know more about spotting male vs female marijuana plants and what the difference is between them, you're in the right place.

Botany 101

large indoor marijuana plant grow house

Most plants reproduce by way of pollination, which can happen a few different ways.

  • Monoecious plants produce both pollen and flowers on the same plant. These plants are also known as hermaphrodites, because they have both male (pollen) and female (buds/flower) reproductive organs.
  • Dioecious plants like cannabis, produce either male or female reproductive organs on each plant. Two dioecious plants, male and female, are needed for reproduction.

Because cannabis grows as either a male or female plant, we can isolate how each sex of the plant grows independent of the other.

Seeds Unless You Separate the Sexes

cannabis seeds and cannabis leaf to be grown into either male vs female marijuana plant

Already, there are huge known benefits to growing female marijuana plants without male interference. One reason is that all the resinous buds that are consumed only come from female marijuana plants.  Removing male marijuana plants from the garden allows female plants to grow large, seedless buds, called sinsemilla.

Having both female and male marijuana plants in your garden will result in cross-pollination, which is what a female cannabis plant needs to make seeds.

Removing male marijuana plants early in the cycle is important for two reasons:

  • It frees up space in your garden, so female marijuana plants grow bigger.
  • It prevents male marijuana plants from pollinating females and developing seeds in the buds.

Cannabis flower that is full of seeds is generally regarded as lower-quality cannabis, when it is intended to be smoked. The presence of seeds in cannabis buds that are smoked is harsh and unpleasant.

However, a grower might intentionally introduce male marijuana plants if they are breeding a new strain or collecting seeds for next year's crop.  New genetics are created by prodigious cannabis breeders who carefully select specific strains to cross-pollinate.

The Future (of Cannabis) is Female

cannabis plant among a lot of other marijuana plants showing there are male vs female marijuana plants

Guaranteed female genetics in a marijuana plant can only be obtained by using feminized seeds or cuttings from a female marijuana plant, also known as a clone.

If you do not have feminized cannabis seeds, then you are working with what are called “regular” cannabis seeds; which may be male or female.

If you’re unsure of your seed type, it’s vitally important to know how to determine the sex of your cannabis plant to grow for maximum yield.  The good news is that sexing cannabis plants is easy if you know when and where to look.

Cannabis plants show their sex in the nodes: the area where the leaves and branches extend from the stalk.

In male marijuana plants, pollen sacs will form underneath the plant's nodes. At first glance, the pollen sacs on a male marijuana plant may appear 'bud-like' or look like a tiny bunch of grapes, but if left unattended, the sacs will swell with pollen.

On female marijuana plants, the female calyx can look like the beginning of a pollen sac. Usually pointed ones tend to be female, but sometimes you have to wait and see a few more flowers to be certain.

Luckily, the pre-flowers of both sexes are visible on the plants weeks before they start serving their reproductive purposes.

Pre-Flowers and Late Bloomers

male marijuana plant sacs

Depending on the strain, sex, and growing conditions, pre-flowers begin to develop four to six weeks into seasonal outdoor growth. You should be able to find the pre-flowers and confidently determine the sex of your cannabis plant by week six of an outdoor grow.

Though there are other methods to determine what sex the plant is, examining pre-flower formation is the most reliable.

A magnifying glass or jeweler's glasses can help identifying the initial pre-flowers that are small and hard to see with the naked eye.

Examine the nodes of each plant and look for the early growth of small (male) sacs or two (female) bracts, which will eventually produce the hair-like stigma.

If your plants do not begin to show pre-flowers even after six weeks, are they just late bloomers? Probably not. This adage only applies to outdoor grows that rely on the sun for light. If you are growing cannabis indoors under a 24-hour light cycle, your plants may never begin to pre-flower.

Gotta Get My 12

close up of marijuana plant

Usually pre-flowering is initiated by adjusting the light cycle to 12 hours of light and 12 hours of dark. This is because cannabis plants are photosensitive and need a few periods of uninterrupted darkness (mimicking the shorter days of Fall), before they being to show pre-flowers.

After two to three weeks of the 12-12 light schedule, most cannabis plants will reveal the first signs of their gender; either they are female marijuana plants and start growing buds (yay!), or if male marijuana plants, start growing balls (boo).

What If You See Both Sexes?

analyzing cannabis plant in a field

When a cannabis plant develops both male and female sex organs, it is a hermaphrodite and should be treated like a male marijuana plant. Hermaphroditic plants can produce enough pollen to ruin your entire garden.

"Herming out," as some call it, can happen from bad genetics or from a plant being excessively stressed. Some common cannabis plant stressors are:

  • Plant damage
  • Extreme Temperature
  • Light Leaks
  • Nutrient deficiencies

It’s important to monitor your plants after they have been exposed to stressors. Being indoors, high temperatures and light leaks are often the culprit. On outdoor grows, a snapped branch might be mended and later show signs of going "hermie."

Cull the Crap, Save the Crop

cannabis field with lots of marijuana plants at sunset

It is wise to destroy any marijuana plants that are showing signs of pollen sacs in a garden; whether they are male or hermaphroditic.  Culling undesirable pollen producing plants is the only way to protect your female marijuana plants from being seeded.

Remember that pollen is extremely potent and very good at traveling. Only keep male marijuana plants in your garden if you're interested in pollinating portions of your crop. Keep male marijuana plants separate from your larger garden and be careful around pollen.

Now that you have a better understanding of the differences between male vs female marijuana plants, you should be able to keep your garden free of any unwanted pollen producing pot plants.

Knowing how to spot the potentially destructive pre-flowers of a male marijuana plant is key to growing excellent cannabis.  Learn more about the best cannabis strains and where to get them at Leafbuyer.