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The 5 Most Common Misconceptions About Feminized Seeds

Debunking the myths about feminized seeds and how they’re made
By Colin Gordon & Ben Owens

The lack of consistent language in cannabis—in conjunction with inconsistent and unqualified information—continues to allow misinformation to run wild. Myths and misconceptions run rampant surrounding different breeding methods, including the process of making feminized seeds. Feminized seeds are seeds produced from two females with a nearly guaranteed chance of female offspring (99%±). 

By breeding with two chromosomal females (XX) we are removing the Y chromosome from the process. 

The difference between breeding with a male instead of two females is that the male’s Y chromosome is part of the equation. When breeding with a male (XY) and a female (XX), you have a 50% chance of the offspring being male or female. When you eliminate the Y chromosome, you end up with 99% or more female (XX) offspring. 

Genetically modified organisms have been modified in a way that does not occur naturally through the introduction of a gene from a different organism. 

#1. Feminized seeds are unstable. 

First and foremost, let’s be specific: 

Genetic stability (homogeneity of expression) will be determined by each parent’s genetic stability and how closely related they are. A plant’s lineage will hint at this, as will the variety displayed in its offspring. Genetic stability is not directly correlated with sexual stability. 

Sexual stability (likelihood of expression of intersex traits) is often correlated with each parent’s sexual stability and how well those genetics interact. 

The most determining factor in sexual stability of a particular genetic is the genetic itself, not the breeding process.* 

Males and females express intersex traits for different reasons; males, from an excess of ethylene and/or a gibberellic acid (GA) deficiency, and females, the opposite, typically an ethylene distribution problem or deficiency triggering intersex expressions. 

There are several ways to make feminized seeds, some are significantly better than others. 

In the past, certain methods have been encouraged and taught that absolutely breed with a higher rate of intersex traits. 

An example would be a book that tells the reader to use plants that are prone to intersex traits soon after ripening to be the source of “female pollen.” This is not a suggested method because that intersex trait will likely breed. 

Although uncommon now, many feminized seeds in the past were made with this method, and, as a result there was a time that feminized seeds did have a higher likelihood of herms. 

Feminized breeding in agriculture has been common since the 1950s and is done using science-based hormone treatments, rather than relying on intersex traits. 

These techniques have increasingly been adopted by cannabis seed makers and breeders to produce feminized cannabis seeds. 

#2: Feminized seeds are genetically modified. 

Feminized seeds are described as such because they are produced without a male, and, doing so, results in offspring without a male chromosome. 

Feminized seeds are made by inducing a hormoal imbalance (typically through an inhibited level of ethylene and/or a surplus of GA). Impeding ethylene’s distribution to the growth nodes results in the production of female pollen. 

#3: Feminized plants are sterile (will not produce seeds). 

This misconception comes from a confusion with the term “sensimilla” (meaning seedless). 

A female plant’s seed-producing capabilities will be determined by those of its parents, regardless of the breeding process involving a male or not. 

#4: Feminized flowers are toxic to smoke. 

The female pollen donor that was reversed to produce pollen using hormones and sprays is considered unsafe to smoke; the offspring are unaffected by this process. 

Once pollen production is induced, and a recipient pollinated, offspring from those seeds and their fruits are perfectly fine. (This is especially true if the pollen was produced without the use of systemic ethylene blockers, which can affect a genetic’s hormone production further down the genetic line). 

#5: All feminized seeds are S1’s. 

As you may recall from our piece on nomenclature, an S1 is any plant that has only one female parent’s set of genes; the female parent pollinates herself or a clone of herself. 

Often, the term “S1" is misused in a broad stroke manner to describe any female seed, which is incorrect. S1’s can only be those female seeds produced by a single parent. 

“Feminized” refers to seed produced using only female parents, including crosses made with two unique female parents to create successive filial offspring (R1, R2, R3, and so forth). 

*Historically, many feminized seeds were made using methods that relied upon intersex expressions and hermaphrodites, which resulted in those traits breeding at higher rates in early feminized seeds. 

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