Find out how to make feminised cannabis seeds


Till the 1990s, any cannabis cultivator was conscious that, in some unspecified time in the future, they needed to separate the female and male crops in the event that they didn’t need the primary ones to pollinate the latter, which ends up in crops utterly filled with seeds. Nonetheless, these had been the times when pioneering seed banks like Dutch Ardour had been revolutionizing the cannabis scene with the delivery of the primary feminized cannabis strains, or in different phrases, seeds that solely become feminine crops. Firstly of the 20th century, many seeds banks had been providing the sort of seeds, feminized variations of classics strains that had been cultivated throughout a few years as common crops.

We’re certain that by now you’d in all probability have grown some feminized seeds, perhaps despite the fact that you’re a purist and the fiercest defender of common seeds. However… are you aware the place feminized seeds come from? Are you aware of the processes utilized by each breeders and growers to acquire them? On this article we clarify all the pieces!

Feminized cannabis seeds high quality management

Benefits of rising feminised seeds

Certainly, the arrival of feminized seeds caused a real revolution inside the cannabis sector. Growers had been now certain that every one their crops can be females, with out the necessity to differentiate between female and male crops or having to take away the males earlier than they might destroy the crops, which gives an a variety of benefits of serious significance:

  • Area and sources saving: no extra rising crops which ultimately shall be eliminated for being males.
  • Reliability: it’s not that almost all crops are feminine, or that they’re genetically extra prone to produce feminine crops. The crops grown from feminized seeds have solely feminine chromosomes (XX), subsequently this methodology is 99% dependable.
  • Sinsemilla crops: by not having males within the develop room, your feminine crops gained’t be pollinated, in order that they gained’t produce any seeds in the course of the flowering interval (one thing that each cultivator desires, except they wish to get hold of seeds)

These benefits had been of nice curiosity for the growers, and shortly feminised seeds accounted for a big portion of the seeds accessible out there. As well as, having the ability to use solely feminine crops (typically recognized and chosen clones) to provide seeds had one other nice benefit for seed producers and breeders of latest varieties: they now not must maintain males of their gene swimming pools! And never solely that… from that second on, any feminine plant they might get their arms on may very well be used as a male to pollinate different crops, thus exponentially rising the chances of making new crosses.

Outstanding Orange Candy feminized from Philosopher Seeds

Excellent Orange Sweet feminised from Thinker Seeds

It’s not stunning, subsequently, that at current, feminized seeds signify just about all of the seeds out there, since they provide quite a lot of important benefits for each skilled and residential growers and breeders, for photoperiod and autoflowering crops. The principle drawback of this methodology is a well-known and hotly debated concern: the growers who purchase the sort of seeds can’t produce their very own seeds within the absence of male crops, so the one manner they’ll handle it it’s utilizing the identical course of to acquire the sort of seeds. However… what are these processes and what are they primarily based on?

Feminine crosses: feminised cannabis seeds are born

As we’ve already talked about, feminized seeds are the results of a course of that reverses the intercourse of a feminine plant, that’s, she is pressured to provide male flowers. This fashion, and as soon as into flowering, the feminine chosen will begin to develop what we all know as male flowers (stamens and anthers), which, similar to male crops, will launch the pollen that may pollinate the feminine crops. What’s then the distinction between a male plant and a reverted feminine plant?

The intercourse of cannabis crops is decided in the identical manner as ours, by means of the so-called intercourse chromosomes or genosomes. Male crops have a few totally different intercourse chromosomes known as “XY” or heterogametic, whereas feminine crops have two chromosomes known as “XX” or homogametic. When crossing a male (XY) with a feminine (XX), we are going to get hold of round half of the crops of every sort of their offspring. In different phrases, when a breeder makes use of a male and a feminine plant, the seeds produced by them shall be roughly 50% males and 50% females.

After this rationalization, lots of you should have already discovered that if we cross two feminine crops (reversing the intercourse of one among them to pressure it to provide pollen), the end result shall be seeds that may produce feminine crops, as there are solely feminine intercourse chromosomes within the equation. If crossing XY with XX produced 50% of every class (female and male), crossing XX with XX will produce crops that solely exhibit chromosomes XX, that’s to say, feminine crops. Regardless of what number of instances we “remodel” a feminine plant right into a male plant, we gained´t be altering their genetic composition, which is able to nonetheless be feminine or XX. This fashion, the pollen produced by this plant will go down feminine intercourse chromosomes solely.

Feminized seeds indoor grow, 100% females plants

Feminised seeds grown indoors, 100% feminine crops

As you possibly can see, and though we usually use the expression “reversing the plant intercourse“, that isn’t precisely what is finished, as a result of the intercourse chromosomes of the feminine plant (XX) haven’t modified, even when we managed to provide male flowers. This “intercourse change” of feminine crops will be achieved in quite a lot of methods, however often with the identical objective: to scale back the extent of ethylene in plant tissues and/or inhibit the ethylene motion, which makes the plant develop male flowers on getting into the flowering interval, as if it had been a male from common seeds. It’s because ethylene is a pure regulator of the intercourse expression in crops!

Let’s see now probably the most standard methods to reverse the intercourse of a feminine plant to be able to produce feminized seeds.

Strategies used to provide feminized cannabis seeds

There are a number of methods to safe {that a} feminine plant produces pollen, and virtually all of them require some sort of chemical that’s usually sprayed on the plant. As soon as sprinkled with the chosen product and beneath a flowering photoperiod, the plant will flower usually, however as a male as an alternative of feminine, producing ‘feminized’ pollen (which solely accommodates chromosomes XX) that can be utilized to pollinate different females to be able to produce seeds. These are a number of the mostly used strategies:

Stress or rodelization

One of many first strategies used to acquire seeds that produce feminine crops was stress or rodelization. There are a number of methods to emphasize the cannabis crops to verify they develop male flowers, similar to by means of temperature, diet, photoperiod, and pH. Nonetheless, supporters of this system usually choose one thing so simple as delaying the harvest 2-Three weeks to be able to pressure the crops to develop a couple of male flowers with out stressing them as a lot as with every of the opposite strategies we have now talked about.

Though this motion will produce far much less pollen than different strategies like STS, will probably be sufficient to acquire a handful of seeds for the home growers to attempt to create their very own feminized crosses. Additionally, the nice benefit of this system is that’s 100% pure, and it doesn´t use any chemical substances. It is a superb various for anybody who simply desires a couple of seeds and desires to maintain it easy with none formulation or laboratory merchandise. Nonetheless, keep in mind that that is the one methodology listed on this put up that will produce some crops with hermaphroditic traits.

Male flower produced by rodelization

Male flower produced by rodelization

STS or silver thiosulfate answer

With none doubt, probably the most generally used strategies for each producers and seed banks. It is a answer made from distilled water, silver nitrate and sodium thiosulphate (generally known as sodium hyposulphite) that, after being sprayed on the feminine crops, inhibits their ethylene motion ensuing within the formation of male flowers as soon as flowering has been induced. STS is comparatively straightforward to arrange, though its lifespan after combining the 2 elements is kind of restricted, barely a couple of days so long as it´s nicely preserved (in a darkish and funky place).

It is very important point out that you could not eat any a part of the crops sprayed with the sort of product, though that may be bizarre, because the crops have “change into” males and gained´t produce any buds. Nonetheless, you shouldn’t use the reverted crops to make resin extracts; the perfect factor is to discard them after harvesting the pollen. Each elements, sodium thiosulphate and silver nitrate, are additionally used for photo-development.

Colloidal silver

That is one other strategy to revert the intercourse of the crops, however this time utilizing a answer made from 30ppm colloidal silver (which you could simply discover in lots of pharmacies and in addition on-line) and distilled water. The answer have to be utilized for a couple of days till the plant begins producing male flowers, one thing that it´s not needed with STS, the place typically one single utility is sufficient.

Colloidal silver is fashioned by electrically charged silver nanoparticles and has antibacterial and antifungal properties. This product was launched out there in 1980 for therapeutic use. Nonetheless, as with STS, it is best to do away with the sprayed crops as soon as their pollen is harvested, as colloidal silver is absorbed systemically by the plant and stays in its tissues.

This sativa plant treated with STS started flowering as a female but soon developed male flowers

This sativa plant handled with STS began flowering as a feminine however quickly developed male flowers

Silver nitrate

It is a methodology researched by Mohan Ram, who additionally performed intensive investigations on plant intercourse reversal with STS. In response to his findings, sodium thiosulphate (STS) is simpler in producing male flowers and viable pollen in feminine crops. Most likely due to this, silver nitrate is blended with sodium thiosulphate, as an alternative of utilizing it in isolation.

Gibberellic acid

Gibberellins are plant hormones that assist regulate varied processes associated to the event of the crops. There are a number of sorts of gibberellins accessible out there, though the most typical and efficient is gibberellic acid or GA3 (Gibberellin GA3). This product is utilized in a really related strategy to colloidal silver, sprayed on the crops throughout a number of days earlier than switching the photoperiod over to flowering.

It’s price stating that one of many uncomfortable side effects of gibberellic acid is a big stretching of the handled elements of the plant, so don’t be shocked if this occurs to your crops! The beneficial dose to attain the perfect outcomes is roughly 100ppm.

City legends and lies about feminized seeds

Even if, after twenty years of cannabis cultivation, most of the false myths surrounding feminized seeds have been debunked, infrequently we nonetheless hear some arguments like those proven under. As is commonly the case, many of those tales are unfold by individuals who have by no means grown the sort of seeds or have none or very restricted expertise with them. Ignorance is at all times a nasty factor, and that’s why we wish to emphasize a number of factors in relation to feminized seeds and the myths that always go together with them; myths similar to the next:

Feminized seeds produce hermaphrodite crops:

The issue with monoecious hermaphrodite crops has extra to do with the mother and father used (and in the event that they exhibit any hermaphrodite trait) slightly than with the kind of seeds produced. If to create a feminized seed you employ a feminine plant with a bent to provide male flowers, a part of its offspring will doubtless inherit that attribute, whether or not the stated feminine plant is used as a pollen donor (after reversing its intercourse) or as a recipient of pollen (letting it flowering as regular).  But the identical factor occurs when producing common seeds: if the male or feminine mother and father should not secure on this respect, neither shall be their offspring (or no less than a part of it).

Marijuana and hermaphroditism

Feminized seeds produce mutant crops:

Nothing may very well be farther from the reality. It’s true that generally some crops develop bizarre traits or mutations, though this additionally occurs with common seeds. Sadly, there appears to be not sufficient research evaluating the ratio of specimens with mutations of 1 or different sort of seeds; nonetheless, given the thousands and thousands of feminized seeds which have been germinated within the final 20 years, if mutations would pose an issue, the amount of feminized seeds offered will surely not be so excessive, and this is able to be a “public safety” concern inside the cannabis sector, each for the growers and the producers of the seeds.

Feminized seeds have chemical substances:

That is one other lie that some folks consider. Because it’s been talked about earlier than, a feminine plant is sprayed with some chemical substances to be able to inhibit its ethylene motion. After a couple of weeks of this and as soon as within the flowering interval, the plant will produce male flowers and pollen, which shall be harvested to pollinate the feminine crops designated to provide seeds. As soon as the seeds are fashioned, they’re collected and packed instantly, in order that they don’t come into contact with any chemical substances or the crops that produce seeds, nor, in fact, with the seeds themselves. Additionally, to produce cannabis seeds, you usually want two separated indoor cultivation areas, one for the reverted crops (handled females) and the opposite for the females to be fertilized to provide the seeds, so the latter can’t get “contaminated” with any chemical substances.

Feminized seeds are GMOs:

As soon as once more, it is a false assertion. We have now already identified that through the use of these intercourse reversal strategies we inhibit the ethylene motion within the feminine plant, and certainly not the seeds (or crops) are genetically modified. The intercourse chromosomes of the feminine plant transformed right into a male plant are nonetheless feminine (XX), nothing has modified at a genetic degree.

We hope you discovered this text attention-grabbing; even right this moment, many individuals are nonetheless unaware of the intriguing course of behind the sort of cannabis seeds. Don’t hesitate to go away your feedback; we shall be delighted to reply them.



  • Marijuana Botany, Robert C. Clarke
  • The Hashish breeder’s Bible, Greg Inexperienced
  • The Hashish develop Bible, Greg Inexperienced
  • Breed your personal vegetable varieties, Carol Deppe
  • Induction of Fertile Male Flowers in Genetically Feminine Hashish sativa Crops by Silver Nitrate and Silver Thiosulphate Anionic Complicated, Mohan Ram, Sett R.


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