Identifying Hermies and Males in the Cannabis Growroom

By Lee G Lyzit
Published: April 20, 2023 | Last updated: April 20, 2023 09:22:24
Key Takeaways

Unless you’re breeding cannabis cultivars, males and hermaphrodite plants are a big problem in the growroom. Learning to identify the signs of these plants early on is essential or they will quickly fertilize an entire crop.

Cannabis falls into a grouping of plant species known as dioecious. Dioecious plant species make up around five percent of all flowering plant species. Unlike monoecious plants, which have both male and female reproductive organs on the same individual plant, dioecious plant species have separate male and female plants. Cannabis growers who start from non-feminized seed will have a 50/50 chance of growing a male or female plant. Unless interested in breeding, cannabis cultivators should remove all male and/or hermaphrodite plants and focus on growing unfertilized female plants, also known as sinsemilla.


Female cannabis plants create flowers that contain higher concentrations of many of the sought-after cannabinoids, including THC and CBD, than their male counterparts. When a flowering female cannabis plant comes in contact with pollen from a male plant, it will begin to produce seeds. Seeds in a cannabis flower create a harsher smoking experience and also diminish the overall amount of cannabinoids in the flowers. Once fertilized, the female plant will put its energy into creating and protecting the seeds. This diverts precious energy that could otherwise be contributing to more cannabinoid and terpene production. To grow a high quality sinsemilla, a cultivator must identify and then remove any male or hermaphrodite plants from his or her cannabis garden. Early detection is key, as pollen from a male or hermaphrodite plant can fertilize an entire cannabis crop in a short amount of time. Unless the cultivator is breeding cannabis, male and hermaphrodite plants should be removed immediately after identification.

Identifying Female Cannabis Plants (Sinsemilla)

female cannabis plant


There are several tell-tale signs a grower can look for when identifying the sex of a cannabis plant. Female cannabis plants will typically start to show their sex in the pre-flowering stage. This is generally after five to six weeks of vegetative growth or after the first one to two weeks of flowering growth (a 12 hours on/12 hours off light cycle). Identifying the sex of a cannabis plant becomes much easier once the flowering light cycle has been initiated. For outdoor cannabis gardens, the plants will normally begin their flowering stage after the summer solstice, when the daylight hours start to drop below 14 hours of light.

Female cannabis plants display unique reproductive organs that can be identified fairly easily with some practice. They produce stigmas that protrude from a green calyx starting at the nodes (base of the branches). This female sex-organ structure is known as a pistil. The stigmas look like a pair of white hairs and typically grow in a “V” shape from the calyx. If the stigma comes in contact with pollen from a male plant, the flower will become fertilized and create seeds.

Identifying Male Plants

male cannabis plant

Male cannabis plants do not produce stigmas and calyxes, but, instead, create pollen sacs. Male cannabis plants can begin their pre-flowering cycle as soon as three to four weeks after seed. They will also show their sex in the first one to two weeks of the flowering stage of growth (12/12 light cycle). The earlier a grower can identify a male plant, the faster he or she can remove the plant from the garden and avoid fertilization. The most obvious sign of a male cannabis plant is the formation of tiny ball-like structures at the nodes. These tiny balls are actually pollen sacs housing pollen grains. Once the pollen sacs are open, they will pollenate any female cannabis plants within a two-mile radius. In other words, if there is an active male plant in your indoor garden, all the female plants will likely be fertilized. When a male plant is identified, it should be completely removed from the rest of the garden and disposed of a distance away.


How to Breed Your Own Cannabis Strain
Blurring the Lines Between Indica and Sativa
7 Things to Know Before Growing Autoflowering Cannabis

Identifying Hermaphrodite Plants

hermaphrodite cannabis plant


Cannabis has an incredible evolutionary trait which allows it, under certain circumstances, to create both female and male flowers. It is believed this trait is far more likely to occur during times of stress. In stressful situations, a cannabis plant may become a hermaphrodite (or hermie) to ensure reproduction. Another reason for cannabis hermaphrodites is simply bad genetics. This is one of the most compelling reasons why cannabis growers should rely on reputable breeders with solid stock.

Hermaphrodites can be a little tricky to identify, but, like male plants, should be removed as soon as they are discovered. Like a male plant, a hermaphrodite has the ability to create pollen, which means it has the capability of fertilizing any and all female plants in the vicinity. There are two types of hermaphrodites growers should be aware of: true hermaphrodites and mixed-gender (a.k.a. “banana”) hermaphrodites.

True Hermaphrodites

True hermaphrodites will have both male and female flower structures on different nodes of the plant. Typically, a true hermaphrodite will display female flowers on some nodes and male flowers on others. In some cases, a node may have both male and female flowers developing side-by-side. True hermaphrodites will display their sex organs about the same time as male and female cannabis plants. True hermaphrodites are the reason why it is so important to continue to monitor a new strain of cannabis in your garden, as it may be falsely identified as a female if the pollen sacs are not detected.

Mixed-Gender, or “Banana,” Hermaphrodites

Mixed-gender, or “banana,” hermaphrodites can be a little more difficult to identify. These hermaphrodites do not create separate male flowers, but, instead, develop partial male organs (stamen) within the female flower. The stamen will drop pollen onto the buds which, in turn, fertilizes them. The male stamen developing on female flowers look like small bananas, hence the name “banana” hermaphrodite. These hermaphrodites can be tricky as they can develop later in the flowering cycle than true hermaphrodites. Always be sure to monitor any cannabis strain that is new to the garden throughout the entire flowering stage to be sure no “bananas” develop.

How to Avoid Hermaphrodites

First and foremost, the best way to avoid hermaphrodites is to only purchase and grow quality seeds from a reputable breeder. The second most important factor to avoiding hermaphrodites is to eliminate or reduce any stress on the cannabis plants. Extreme temperatures, diseases, and nutrient deficiencies can all trigger a cannabis plant into becoming a hermaphrodite. Put another way, providing a consistent environment, within the optimal range of temperature and humidity, along with a complete, quality feeding program is a solid defense against developing hermaphrodites in the growroom.

Feminized Cannabis Seeds

One fantastic way to greatly reduce the chance of any male or hermaphrodites in your garden is to purchase and grow feminized seeds. Over the years, breeders have developed techniques to feminize cannabis seeds, which produce female plants at a 98 percent success rate. In contrast, unfeminized cannabis seeds will produce offspring that are around 50/50 male to female. Feminized seeds help when growing only sinsemilla; however, there is still a small chance for a male or hermaphrodite, so it is important to monitor the plants.

Whenever you grow a dioecious plant species from seed there will be a 50/50 chance for male and female offspring (feminized seeds are the exception). Since cannabis is dioecious and cultivators typically only want female plants, the ability to accurately sex the plants becomes an important part of the cultivation process. Like other issues in a cannabis garden, early detection and action are the keys to controlling and/or eliminating problems. If a cannabis grower is paying close attention during the pre-flowering stage, males and hermaphrodites can be identified and removed before pollination occurs. And, as long as a grower is aware and monitoring his or her flowers, even banana hermaphrodites can be recognized and removed before any damage is done. Understanding how to “sex” cannabis plants allows a grower to quickly remove any unwanted plants and focus on what most cannabis cultivators strive to achieve: large, sticky, potent sinsemilla.


Share This Article

  • Facebook
  • LinkedIn
  • Twitter

Written by Lee G Lyzit | Grower, Writer

Profile Picture of Lee G Lyzit

Lee G. Lyzit has been involved in the cannabis industry for nearly 20 years. His passion for natural healing motivates him to learn as much as he can about the miraculous cannabis plant. Lee’s knowledge of cannabis gardening stems from his own extensive cultivation experiences and his past work as a hydroponic shop owner and manager.

Related Articles

Go back to top
Maximum Yield Logo

You must be 19 years of age or older to enter this site.

Please confirm your date of birth:

This feature requires cookies to be enabled