We provide a feminized seeds definition and talk about them in more detail so that you know how to grow feminized seeds for the best results Male cannabis plants produce very few cannabinoids, which means growers potentially have to scrap 50% of their crop. For this reason, we have developed feminized seeds. But just what are feminized seeds, and where do they come from? The answer is a remarkable feat of genetics and horticulture. “Feminized seeds run the risk of catastrophic failure” Back in the 1980s, the landscape of cannabis growing was inevitably changed by the discovery of how to make feminized seeds. As every
Feminized Seeds Explained: Let’s Separate Fact from Fiction
What is a feminised weed seed? We try to answer this question and clear some of the misconceptions that even seasoned growers have
Today, feminized seeds are everywhere. You can grow weed for years without actually laying your eyes on anything else. As if marijuana were a single sex (female) plant all along. But it isn’t so, and it’s best to have clear answers to the following questions about feminized seeds: what does it mean and what exactly to expect from them? These questions are not just theoretical, but have a real practical value.
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What is a Feminised Weed Seed Exactly?
Here’s a very short and pragmatic feminized seeds definition for you. Feminized seeds are cannabis seeds that turn into female plants only. This is how they differ from regular seeds which can turn either female or male. Now let’s talk about it in more detail.
As you may know, cannabis has two distinct sexes. Take a bunch of seeds from plants grown in nature and sow them. Some of them will grow into male plants and some — into female plants. The ratio will be around 50/50. Growers call such natural seeds regular.
For some time, regular seeds were all that was available to weed growers. The first small batches of seeds that deserved the name ‘feminized’ started to appear in the beginning of 1990s in Amsterdam. It was the founder of Dutch Passion who first offered them. Today, Dutch Passion is one of the oldest commercial seed banks that are still around.
The feature of this new type of seeds was that they grew into female plants more than 95% of the time. In fact, closer to 100%. It was a God’s gift for bud growers because now they didn’t have to throw away half of their plants at the beginning of the flowering. They knew that there would be only females in their garden and that they would harvest buds from every seed they had sowed.
Are Feminised Seeds Always Female?
Well, ideally they should be, and serious breeders go to great lengths to ensure that ALL their feminized seeds become female, but in reality they never are. Not 100%. Even the best feminized seeds produce males occasionally. Fortunately, such occasions are rare. Statistically speaking, you should grow close to a hundred of plants before you see a male intruder in an all-girl team. So can feminised seeds turn male? Yes, they can, but it’s highly unlikely for you to have this issue with your very first attempt.
What Makes a Feminised Seed?
The feminized seeds definition we’ve given above doesn’t explain how exactly breeders manipulate the beans into producing only females. In a few words, cannabis plants can change their sex in response to stress or when exposed to certain chemicals. It means that females can turn into males and produce pollen sacks instead of flowers.
Growers have long noticed this phenomenon. It’s called hermaphroditism and is a very unwelcome thing in your garden because you want buds without seeds and ‘female’ pollen will make all the buds go to seed and your whole crop will be ruined.
So, growers had been fighting ‘hermies’ for a long time, but they didn’t immediately realize that the seeds that they got in their buds because of female pollen would grow into female plants only. Well, hermaphrodite plants to be exact. Meaning that they will mostly produce female buds, but also some pollen sacks whenever they experience too much stress.
Believe it or not, the very first batches of feminised seeds marketed by Dutch Passion in the early 90s were made exactly this way. The plants were stressed to the point that they hermied and then hermies-prone seeds were harvested and sold. No wonder that those initial barbaric methods gave feminized seeds a bad reputation and still make some purists use only regular beans. You can read more about ‘feminised seeds vs regular’ controversy in a separate post.
Feminized Seeds Without Hermies Are the New Norm
The time when ‘fems’ and ‘hermies’ were practically synonyms is long gone. Now, breeders produce feminised seeds in a totally different way. They use special chemicals for this. It could be gibberellic acid or silver thiosulfate or such a simple solution as colloidal silver water made with the use of a homemade 9V battery feminisation kit. Anyway, none of these techniques involves any stress. It means that the resulting seeds are no more prone to hermies than their regular counterparts.
There is even a special method to make sure that a plant you choose for making feminized seeds isn’t predisposed to hermies at all.
How to Select a Feminized Plant That Won’t Hermie?
It works like this. You take a bunch of regular seeds, grow plants from them, put them into the flowering mode, and when they reveal their sex, discard all males. As for the remaining females, you wait till they begin to flower in earnest and then start to stress them. You can doi it by constantly changing the light cycle: when today it’s 12/12, tomorrow — 18/6, then — 14/10, etc. All weaker genetics—when ‘punished’ this way—will turn hermies at some point. And the ones that stay female despite all the stress are definitely keepers. Meaning they are your best choice for feminized seeds production.
Do Feminized Seeds Produce Different Phenotypes?
Making seeds that always turn female and making seeds that grow into very uniform-looking plants are two completely different things. So, with feminized seeds, a breeder never guarantees that you will get only one pheno. The phenotipic variance can be as huge as with regular seeds. And if you want feminised seeds that don’t have different phenotypes, make sure that the breeder or reviewers describe the strain as stable.
So, we did our best to define feminized seeds’ meaning. Now let’s take a few moments to dispel some misconceptions that people have about this type of marijuana seeds.
Feminized vs Autoflowering
Some people, when they choose a strain, wonder what they should rather buy: feminized seeds or autoflowering. As if these were opposing terms. In fact, they are not. The confusion is understandable: seed shops offer seeds in two large categories:
- feminized autoflowering seeds -> usually shortened to just ‘autoflowering seeds’,
- feminized photoperiod seeds -> usually shortened to just ‘feminized seeds’.
The fact that the words not marked in bold are too often omitted has created this confusion. In fact, there are also regular autoflowering seeds and regular photoperiod seeds, but neither category is very popular. Most newbies don’t even see them when they shop for seeds. All they see are the words ‘feminized’ and ‘autoflowering’, and so they feel like they should choose either one or the other. The good thing is you can have both. Autoflowering feminized seeds produce only girls, and they all start to flower automatically.
This confusion aside, we’ve written a separate post discussing pros and cons of autoflowering vs non autoflowering seeds.
How to Tell Feminized from Non Feminized Seeds
Another misconception is that feminized seeds somehow look different than other types of seeds. Not by a long shot. A seed is a seed. It can be small or large, or it can look mature or immature, but, other than that, you can’t tell anything about the seed’s genetics by just looking at it.
It can be medical cannabis or hemp, sativa or indica, an auto strain or a photoperiod one, it can be a high THC or low THC variety, or CBD rich etc. and all of them will look just the same.
And if you insist on knowing what type of seeds you have—feminized or not—the only sure way is to wait till they flower.
Do Feminised Plants Produce Seeds?
If feminized seeds catch some pollen, they do produce seeds. After all, they are feminized, not castrated. The reason why people have seed-free harvest of buds from feminised seeds is because they don’t have any males in their grow room and no male pollen. But if you get some pollen inside your grow space (from outside or from hermies), your plants will get pollinated, no matter feminized or not. So, if you bought only fems and still your feminised plant has seeds, look for the source of pollen.
How to Grow Feminized Seeds
There is a whole group of questions from novice growers regarding germination and planting of feminised seeds, their grow time and flower time, light cycle, phenotypes and what not.
We’ve already said that feminized seeds look exactly like non-feminized. Well, they also grow the same and should get the same treatment as regular seeds. The only real difference is that you won’t have to cull the males when the plants in your garden show sex.
Maybe there is one more difference. If the breeder hasn’t done his job properly and his fem seeds genetics are unstable, the seeds will be more prone to become hermaphrodites. In this case, take extra care not to stress your feminized plants at any point of their life cycle. Other than that, take care of them just the normal way and you’ll be alright.
Feminized Cannabis Seeds Explained
L ike many living things, cannabis plants come in two sexes, male and female, which blend their genetics through pollination to produce seeds. These seeds then, have about a 50% chance of inheriting the sex of either parent. However, male cannabis plants produce very few cannabinoids, which faces many growers with the prospect of scrapping about 50% of their crop (unless, perhaps, they’re making their own rope). For this reason, we have developed feminized seeds. But just what are feminized seeds, and where do they come from? The answer is a remarkable feat of genetics and horticulture.
What are Feminized Seeds?
Feminized seeds are cannabis seeds genetically guaranteed to grow into a female plant. Female plants produce far more THC and CBD than their male counterparts, but once a female plant is fertilized, resources and energy are diverted from growing rich, sticky flowers, to growing a healthy crop of seeds instead. Those seeds are, of course, wonderful and necessary, but they may inherit the gender of either parent, and, as we have seen, males are nearly useless for harvesting cannabinoids.
Feminized sees will always guarantee a female plant, ensuring growers a plant that will produce cannabinoids. photo credit
When growing for cannabinoid production, pumping water, fertilizer, and time into your plants only to find half are male can be frustrating to say the least. A single male plant can pollinate an entire grow room, leaving whole crops producing seeds instead of flowers. Additionally, inspecting your plants for male attributes and removing them from the grow room takes time and attention that could otherwise go to treating female plants. For this reason, we have learned how to breed feminized seeds – seeds that we know will grow up to be female, and produce lush flowers rich with therapeutic cannabinoids.
How Feminized Seeds Are Made
Female seeds must come from two female parents, which on the surface sounds impossible. But under extreme circumstances, female cannabis plants can produce their own pollen. So the first step toward feminized seeds is inducing pollen production on a female plant.
The primary method is to douse the flowering sites with a solution of colloidal silver, or less commonly, with gibberellic acid, for about two weeks once the flowering stage has begun.
These chemicals will suppress the hormone ethylene, which causes the plant to produce male characteristics instead, including pollen sacs. And since the plant is still genetically female, the pollen within will carry 99% female genetics (a small margin of mutation is unavoidable). This pollen can then be harvested and applied to a flowering female plant to produce seeds with purely female genetics.
The less common, but more natural, method is called “rodelization,” often favored by organic growers. Near the end of a cannabis plant’s life cycle, unfertilized females will begin to express male pollen production as a final effort to continue their genetic line. This usually occurs after the prescribed time frame for harvesting, but not always. In fact, many growers keep a sharp eye out for these “nanners” – the banana-shaped growths that protrude from flowers – because they are capable of fertilizing other plants as well, thus halting flower production.
There is a debate among growers about the viability of this method because some believe hermaphroditic plants primarily produce hermaphroditic offspring. Others insist that offspring are not more inclined to be hermaphrodites, but rather may be more easily induced to be hermaphrodites, and that hermaphroditism has less to do with genetics than external stressors (high heat, nutrient lock, physical damage, etc.). Regardless, most growers agree that rodelization is less effective and carries a higher risk of accidental pollination. For this reason, it is more often used by more experienced or meticulous growers who want to maintain the organic integrity of the plant.
Feminized seeds have become the industry standard, especially for home growers who do not have the space or resources to scrap half of a crop that turns out to be male. Many sites now default to offering feminized seeds, some growers have undoubtedly planted them without fully understanding the science behind them. And one thing that makes these seeds so popular is that you can, you can grow them without knowing what they are or how they exist, and they will still deliver a lush, low-maintenance cannabis plant.
Interested in growing your own cannabis? Click here to purchase seeds and start your journey.
This is also a great process to practice if you want to take your growing skills to the next level. So next time you find some nanners growing in your bud, don’t panic, but rather appreciate the opportunity that has presented itself, and try breeding your own feminized seeds.
Do you prefer to grow with feminized seeds, or have you ever made you own? Share your experiences in the comments!
Trevor Ross is a writer, medical marijuana patient and cannabis advocate. He holds an MFA in writing from the School of the Art Institute of Chicago. He has previously worked as a copywriter, a teacher, a bartender, and followed Seattle sports for SidelineBuzz. Originally from Washington state, you can find him now working in his garden or restoring his house in Scranton, PA, and he can be reached through LinkedIn.
“Feminized seeds run the risk of catastrophic failure”
Back in the 1980s, the landscape of cannabis growing was inevitably changed by the discovery of how to make feminized seeds. As every cannabis grower knows, only female cannabis plants produce flowers, while male plants are just used to make the pollen necessary for female plants to produce flowers with seeds. This groundbreaking discovery meant that every grower was sure that every seed they were planting, would produce consumable flowers. Even though this aspect surely advanced cannabis cultivation as a whole, its application to large-scale growing can be particularly tricky.
“There is an old saying that goes: it seemed a good idea at the time,” Jason Talmage explains. “I learnt the hard way the pros and cons of feminized seeds. With all due respect, growers who promote them just don’t have enough experience with feminized seeds.”
Instability of feminized seeds
Jason further explains that feminized seeds do not offer stable genetics, which eventually means that they may develop hermaphroditism. “Feminized seeds are just unstable,” he says. “Therefore, if they get stressed and develop hermaphroditism, they might ruin the whole crop. This is an incredible danger for large scale operations. If a whole crop is made from feminized seeds and just one plant becomes a hermaphrodite, then you might have to throw away everything, resulting in an enormous loss, not only with regards to that specific crop, but also with regards to the logistics of the entire operation. Indeed, without proper cleaning after a seeded crop, it may take anywhere from weeks to months before it is safe to grow in again. To fix this, one could use fresh water to clean the room as it deactivates the pollen. On the other hand, another method would be to utilize a pH-balanced freshwater foliar spray every five days on plants themselves which would help to mitigate the problem if a crop goes to seed and the company cannot just start over a new planting.”
The importance of data collection
According to Jason, the only way to prevent this from happening is to have an R&D department that can develop stable genetics and then carry out tissue culture. “The other thing with feminized seeds is that you are never sure if the plant will be stable,” he says. “They are not like clones that are all the same, but each seed is an individual plant with specific characteristics. If you take a bunch of feminized seeds and do some stress tests, it might be that you never get a hermaphrodite. But, in the moment you plant them and maybe there is some light leaks in the greenhouse, for instance, then one plant might develop hermaphroditism. These sorts of issues might happen in greenhouses, especially with those infrastructures that are not properly sealed. For example, the blackout necessary to induce the flowering to cannabis plants can be very expensive, so some people just use plastic to cover the facility. Needless to say, the chance of getting light leaks that could stress the plants is incredibly high.”
At the same time, not only light leaks can cause stress to plants. “It can be everything, such as root aphids, heat stresses, nutrient deficiencies, pH fluctuations, overdefoliation or overwatering or underwatering. The problem is that signs (symptoms) don’t manifest for some of these issues until days or weeks after the original stressor which by then it is too late to prevent the plant stress. When symptoms manifest on the plants, growers will often look for something that went wrong in the previous couple of days as opposed to analyzing long term data to find the original stressor leading to inaccurate diagnoses. This also shines a spotlight on why intense and comprehensive data collection is critically important in all phases of the process.”
Better go for another route
“Thus, Jason concludes that it doesn’t make much sense for large cannabis companies to opt for feminized seeds. “Feminized seeds run the risk of catastrophic failure,” he says. “I have seen hermaphrodite crops that were still sellable too, but then you have to spend more time and money to inspect each and every single plant to see which one meets the quality standards. If a large company wants to be sure about the outcome of its cannabis crop, then it has to invest in an R&D department that can ensure stable genetics. Many companies nowadays are going for this, as the competitiveness of the market and the razor-thin profit margins do not allow growers to make mistakes.”