“A single hermaphrodite can pollinate an entire grow room, rendering the cannabis flowers useless.” Learn more about hermaphrodites in the world of cannabis here. I have an indoor growroom and in my recent harvest I found seeds in the buds, but I’m sure there are no male plants in the room. This is what you need to know to distinguish Male, Female and Hermaphrodite cannabis plants in your garden or grow room – and avoid seeds in your harvest.
Hermaphrodites: A word derived from the names of the Greek deities Hermes and Aphrodite; hermaphrodite is meant to convey the presence of both sets of reproductive organs. Cannabis, as some unfortunate growers may know, can develop this trait if stress occurs in sufficient quantities. A single hermaphrodite can pollinate an entire grow room, rendering the flowers useless. Light stress is the most common culprit, in which light leaks and broken timers can spell disaster! Check for any holes in your sealed grow room, and ensure timers are operating correctly to spare yourself this pain. However, hermaphrodites are the objective for some gardeners. Hermaphrodites are an essential aspect for the production of feminized seeds. In this case growers will spray a solution of colloidal silver on their plants during the first weeks of the flower cycle. The silver solution interrupts the production of female reproductive organs leaving a hermaphrodite. These plants are then left to self-pollinate and produce seeds that are 99.9% female, while maintaining the genetic traits of the parent.
I have an indoor growroom and in my recent harvest I found seeds in the buds, but I’m sure there are no male plants in the room. I’ve heard that light leakage can cause plants to become hermaphrodites. Is this true, and if so, do you have any tips for avoiding this?
Cannabis plants are monecious. This means they have the ability to be either male or female. Or in the case of hermaphroditism, they can be both. The reason to make sure there are no males or hermaphrodites in your garden is because male flowers make pollen. When pollen touches the white hairs on a flower, it makes a seed, and seeded weed gives you headaches. Even though there are reasons in nature hermaphroditism could be important, such as continuing the species in case there is no male present, hermaphroditism is generally a bad thing when talking about cannabis plants.
Light poisoning is the most common cause for a normal plant to hermaphrodite.
Light poisoning refers to the flowering night cycle of a plant being unnaturally interrupted with light. The best way to prevent this is to close yourself inside your darkened room during the daylight, and then after allowing a few minutes for your eyes to adjust to the dark, check for any light leaks from covered windows, door jams, etc. Also cover all timer and appliance lights with tape.
Negative stressors can combine with small interruptions of the light cycle to cause hermaphroditism, especially with less-stable, clone-only hybridized strains. When the night cycle is abnormally interrupted, it sends a mixed hormonal signal to the plant. This can cause a full female plant to throw some male flowers. Male flowers are easy to identify, especially when side by side with female flowers. Male flowers look like small bunches of bananas, which will take a week or two to swell before they burst and release their pollen.
Finding a hermaphrodite in your growroom can happen at any stage of the flowering cycle and is indicated by the presence of male flowers growing on the same plant as female flowers. As with all species in nature this can occur in varying degrees. A plant can become slightly or majorly hermaphroditic. In cases where singular male flowers are found between the branch and stalk nodes, you should be diligently removing them as they grow. You must re-inspect the plant top to bottom every few days to be sure pollination and seeding doesn’t occur. If you find male flowers (anthers) actually growing from within the female flowers (buds) the situation is a little more dire. You can still remove all the male anatomy as it appears, but it will be harder to find and much more prevalent. This is a horrible discovery that leads to a tough decision: Should you let the plant live and risk the whole crop being ruined by seeds?
In either case, once hermaphroditism has compromised the safety and purity of your sensimilla, the plant should not be propagated further. Remember, once a hermy, always a hermy. The plant pictured here is in the tenth and what should have been the final week of ripening, but a timer failed and one light stayed on continuously for almost two weeks, causing this vegetative regrowth. Because the light was continuous, the plant made no pollen. This method of re-vegging can be used to save a flowering plant you have no copies of, but be careful, as this may cause some strains to hermaphrodite.
Purposefully causing a plant to hermaphrodite is called selfing. Gibberellic acid or colloidal silver is typically sprayed onto the female plant. This technique is used to make feminized seeds and uses the plant’s ability to be both male and female to force a female plant to produce male flowers. The pollen contained in these male flowers can only produce female seeds. Just keep in mind that feminized plants should not be used for breeding, as they were produced without a true male, making them genetically inferior.
How To Spot: Male, Female and Hermaphrodite Cannabis Plants
You don’t have to be an expert on the plant to at some point have encountered the term ‘feminized’ in relation to cannabis seeds. As the name suggests, this means cannabis plants can be either female or male and in some cases have both sexes. This is what you need to know to spot Male, Female and Hermaphrodite cannabis plants in your garden:
Male Or Female Cannabis Plants
Before we dive into the more complicated matter when it comes to sexing a cannabis plant, let’s start with some basics. Cannabis plants are so called ‘dioecious plants’ (‘di-‘ is ‘two’ in Greek; ‘oikia’ means ‘house’). This means they produce either male of female reproductive organs, known as the flowers. In contrast to ‘monoecious plants’, which produce two different types of flowers on the same plant.
The cannabis plants most consumers know and love are often female. As these are the plants that produce the smokeable flowers – the dried buds – but which can also be grown at home. These weed flowers, buds, or ‘colas’ are covered in trichomes / resin which holds the plant’s active components, like cannabinoids and terpenes. Male cannabis plants however are less popular with consumers, as their only task in life is to release pollen into the air.
Feminized Cannabis Seeds
When pollen from a male cannabis plant reaches a female cannabis flower, the female flower will start producing seeds with traits from both plants involved. That’s great for growers that like crossbreeding strains and develop their own cannabis varieties. But if you’re growing for your personal consumption, you might want to avoid pollination. Not only do seeds add a harsh taste to your smoke. Producing them also takes a lot of energy from the plant. Costly energy that should rather be put into the development of cannabinoids like THC and CBD.
The best thing you can do to guarantee you’ll grow female cannabis plants, is to purchase feminized cannabis seeds. In contrast to regular cannabis seeds, which will grow 50/50 males and females, feminized seeds guarantee for 98% to grow into female cannabis plants.
So even if you use feminized seeds, it is advised to keep a close eye and determine the sex of the plant as soon as you can. As there’s always a small chance at finding a male plant in your garden which could screw up your harvest, or for the plant to turn from female to hermaphrodite and develop both sexes on one cannabis plant; as we’ll explain later on.
Female Cannabis Plants
The sex of cannabis plants can be determined by looking for the first signs of bloom on the plant. These are visible a few days to a week after you switch your light to 12/12 and give your plant the sign to switch from the growth stage to the flowering stage of its life cycle . Outdoors, the same signal is given by nature as soon as the days grow shorter than 14 hours after the summer solstice.
Female cannabis plants are easy to spot once they start showing the first signs of flowering
Female weed plants are distinguished by the development of bracts with small white hairs (stigma’s) on their nodes. A node is the part of the plant where branches and leaves emerge from the stem. After a while, the female plant starts pushing out more and more of these hairs until they swell up from the bottom up. This means the plant is now forming ‘calyxes’ that eventually stack up to become the flower as we know it.
Pollination And Seeds
These ‘calyxes’ remain empty as long as the plant is not pollinated by a male plant. When it does get pollinated, these calyxes will fill up to hold and protect the plant’s babies: seeds. It is even thought that the resin on weed plants serves only that purpose in nature: to protect the plant’s offspring from burning in the sun.
Discover our Feminized Chocolato cannabis strain (White Choco x Gelato) here!
Male Cannabis Seeds
Male Cannabis Plants are recognized by the formation of pollen sacs on the plant’s nodes. This happens around the same time as female reproductive organs should be forming. Although female plants tend to develop their reproductive organs a bit faster. Luckily, these male pollen sacs can be distinguished pretty easily. As they look like small balls hanging from the side of the plant; instead of the upward facing hairs from the female plant.
Male Cannabis Plants form small ball-shaped pollen sacs on their nodes
When left to grow, these balls will eventually open up like a flower and release pollen into the air. As we’ve explained, this pollen is only interesting when you’re trying to make your own strains or seeds. If you’re not making seeds, make sure to remove every male plant from your garden or grow room before this happens. Do it with the upmost care, as rocking the plant could force it to release the pollen.
Hermaphrodite Cannabis Plants
The first paragraph of this article explains cannabis plants grow only one set of reproductive organs. Although there is still a ‘but’ to this. Because there always remains the possibility that female cannabis plants form male reproductive organs too. This usually happens when the plant(s) experience excessive stress. And in times of stress, they try to guarantee the survival of their species. Cannabis plants can do so by turning hermaphrodite, or ‘herma’ in grower terms.
Hermaphrodite cannabis plants develop both female and male reproductive organs
Because when cannabis plants turn ‘hermaphrodite’, they do so in order to pollinate themselves. Turning hermaphrodite is an evolutionary strategy of cannabis plants, designed to save the species in hard times.It allows the plant to produce seeds no matter what; even when there are no males around (for example, because the source of the ‘stress’ killed off all male plants).
How To Prevent Stress From Turning Female Cannabis Into Hermaphrodites
Some cannabis strains are more sensitive to stress than others. Stress can arise from a number of sources, from overly enthusiastic pruning and topping to environmental factors like excessive temperatures, water shortage or surplus, soil acidity or overfeeding and lack of nutrients. It is good to know that cannabis is called a ‘weed’ for a reason: this is a hardy species with great natural resilience. Still, most cannabis seeds you can order online are crossbreeds cultivated for specific traits like taste or THC content. Years of crossbreeding and hybridization have created some strains that are more prone to stress than their natural ancestors.
When growing strains that are sensitive to stress, growers run a risk of their cannabis plants developing hermaphroditic traits – like the well-known Original Glue (Gorilla Glue #4). In our online seeds catalogue, you’ll find certain strains that are particularly resistant to stress.
Removing Sex Organs From Hermaphrodite Cannabis Plants
If for whatever reason you do spot hermaphrodite cannabis plants, all is not lost. You just have to act fast and be cautious. To avoid hermaphrodite cannabis plants from pollinating themselves, carefully remove the male reproductive organs that form on the nodes. You can do so by gently taking a pollen sac in between two fingers and twisting/pulling it off. Wash your hands thoroughly before you go near your female plants – you don’t want to cause accidental pollination because of your dirty fingers! This way you can still have a satisfying harvest from any hermaphrodite, without having to pluck the seeds from your buds.
TIP: If you want to try and create your own unique strains, you can learn more about growing regular seeds in this blog.
TIP: For anyone trying to avoid raising hermaphrodites, check our info on the benefits of buying feminized seeds here.