Feminized seeds: definition, feminization methods and benefits

Feminized seeds are selected to produce only female plants, as opposed to ordinary seeds which have a 50% chance of producing male plants.

Apart from the fact that male cannabis plants produce pollen sacs instead of flowers, the presence of male plants around female plants can ruin an entire harvest. This is because male plants pollinate the buds of young female plants. When this happens, the flowers are full of seeds, reducing their quality and value.

Breeders and growers have developed feminized cannabis seeds to meet these challenges. By increasing the likelihood that all your seeds will produce female plants, you eliminate the possibility of getting a male plant that won't produce flowers, and of a male plant accidentally pollinating flower-bearing female plants.

How to obtain feminized seeds

Feminized cannabis seeds are widely available. You can buy feminized cannabis seeds online from seed banks around the world. And if you live where home growing is legal, you should be able to buy feminized seeds from most dispensaries. You can also feminize seeds yourself at your local breeding, For the best feminized seeds, buy from a reputable breeder or seed bank.

How are cannabis seeds feminized?

Feminized cannabis seeds are created through a process of genetic manipulation. Essentially, this involves inducing female plants to produce pollen. Normally, only male plants produce pollen, but if you can get a female plant to produce pollen, you get pollen containing only female chromosomes. There are several ways of achieving this:

• Spray a female plant with colloidal silver as it grows and its transition to the flowering phase. This chemical promotes the growth of pollen sacs, and as this pollen comes from a female plant, it carries female chromosomes. When the plant starts producing pollen, use it to pollinate the flowers of an ordinary female cannabis plant. These pollinated flowers will produce feminized seeds.
• In a process very similar to the colloidal silver method, spray a young female cannabis plant with silver thiosulphate. This chemical suppresses ethylene production, which is necessary for the flowering process. By feeding your female plant with silver thiosulfate, you encourage the plant to produce pollen, which can be used to pollinate other female plants and produce feminized cannabis seeds.
• The third main method is known as «rodelization». This is an all-natural technique, although it does not produce the desired result as consistently as the colloidal silver or silver thiosulphate methods. Rodelization takes advantage of a natural process whereby an unpollinated female plant sometimes organically produces its own pollen sacs. This is the plant's last effort to reproduce itself. With this method, you force a female plant to remain in the flowering phase for long enough for the plant's self-pollination mechanism to kick in. When this happens, you can use the pollen created by the female plant to pollinate the flowers of a normal female plant, which will then produce feminized seeds.

The history of feminized seeds

The colloidal silver feminization technique was popularized in the 1990s, mainly by Dutch breeders. Sensi Seeds is often credited with being among the first seed banks to market feminized seeds on a large scale, in the second half of the 1990s. The technique was initially greeted with scepticism, with many growers fearing genetic instability or an increased risk of hermaphroditism, before becoming the market standard in the 2000s.

Today, feminized seeds account for the vast majority of sales in the world's seed banks, precisely because they enable the production of sinsemilla - seedless female cannabis - without having to master plant sexing.

What's the difference between autoflowering seeds and feminized seeds?

The autoflowering seeds have been bred to enter the flowering phase without needing changes in light to activate flower production. The fact that cannabis seeds are seeds has nothing to do with when the plants enter the flowering phase. Feminized cannabis seeds have been selected to produce only female plants.

Are feminized seeds guaranteed to be female plants?

Although feminized seeds generally produce only female plants, there is no guarantee at 100 %, whether you buy feminized seeds or create them yourself. Occasionally, a feminized seed may become a male plant. That's why it's a good idea to keep a close eye on your plants as they grow. If you see pollen sacs starting to form, remove the plant before it accidentally pollinates and ruins your female plants.

S1 vs feminized crossed an important nuance for demanding growers. A S1 seed is produced by self-fertilization of the same female plant (pollen from the same plant fertilizing its own flowers via rodelization or colloidal silver). It offers great homogeneity, but can fix certain genetic defects. A crossed feminized seed uses pollen from a female plant A to fertilize a different female plant B - it better preserves the genetic diversity of the cross. Serious seed banks generally make this distinction clear in their product sheets.

Do feminized seeds produce seeds?

In theory, plants from feminized seeds should not produce seeds. They should only become female plants, and unpollinated female plants produce buds instead of seeds. Cannabis plants produce seeds when the flowers of a female plant are pollinated by the pollen of a male plant. In the absence of male plants, there should be no pollen and therefore no seed production. However, if you force a female plant to remain in the flowering stage for too long, all is lost and you risk ending up with a rodeal, as shown above.

Are regular seeds better than feminized ones?

Growing cannabis depends on your goals and preferences. There's no inherent reason why regular female marijuana seeds should be considered better than feminized seeds. That said, feminized seeds :

• Maximize yields by reducing the risk of producing an unusable male plant
• Reduces the risk of male plants accidentally pollinating female plants
• Simplify the growing process by making unexpected male plants much less likely
• In many ways, feminized seeds can be a good option for new growers, as they remove some of the guesswork and reduce the pressure to identify and eradicate unwanted male plants quickly and accurately. However, there are no guarantees and new growers still need to do their homework and know how to spot a male cannabis plant.