Cannabis can be either male or female—also called “dioecious”—but only females produce the buds we all know and love. For reproduction, males have pollen sacs and pollinate females, causing female flowers to produce seeds.
Seeds for these varieties are now widely available online and through dispensaries. It should be noted, however, that any plant grown from these seeds is not guaranteed to produce high levels of CBD, as it takes many years to create a seed line that produces consistent results. A grower looking to produce cannabis with a certain THC to CBD ratio will need to grow from a tested and proven clone or seed.
Pros and cons of using cannabis seeds
With cloning, you don’t have to get new seeds every time you want to grow another plant—you just take a cutting of the old plant—and you don’t have to germinate seeds or sex them out and get rid of the males.
Many marijuana growers start autoflowers early in the season, and at a different time than a regular crop, so keep the season and climate in mind when growing and harvesting—your plants still need warmth to grow, and rain can give them bud rot. Consider growing in a greenhouse to protect them.
Growing marijuana takes a certain level of commitment: time, energy, and financial resources, so be sure you can commit to the whole process.
Both substances are a blend of water and fine silver particles, and they work in largely the same fashion. The silver solution impedes the production of ethylene, a hormone involved in flowering. The result is a female plant, but one that produces male flowers with pollen sacs. Since those pollen sacs develop on a plant with only female genetics, female genetics are all they carry. When those flowers pollinate another female plant (one untreated by silver solutions), the resulting seeds are nearly certain to be female.
Treating plants with a silver thiosulphate solution results in seeds that will produce feminized plants nearly 100% of the time, and Kannabia’s breeders have found this method to be the most effective way to maintain the stability of the seeds and future feminized plants.
This article is sponsored by Kannabia Seed Company, an award-winning cannabis seed company headquartered in Spain. Using only the highest quality genetics on the market, their grower-oriented approach has made cannabis cultivation simple and satisfying for growers of all skill levels for years.
How Are Cannabis Seeds Feminized?
If you have more questions about strains or seeds, keep digging through Leafly’s resources. And to learn more about the variety of feminized seeds available to you, visit Kannabia’s website to see its full line of feminized genetics, including strains like Diesel Glue and the award-winning Mataro Blue.
Once those plants are old enough, growers have to go to the trouble of actually determining their sex, monitoring each individual plant to ensure any males are removed before they can pollinate their female counterparts.
Traditionally, the solution to this has been an inelegant one, with many cultivators planting at least twice as many seeds as they hope to harvest with the assumption that about half of them will be useless. However big a harvest you’re looking for, using regular seeds means you’ll have to plant twice that many seeds.
This is why many North American growers are turning to feminized seeds—cannabis seeds that carry only female genetics, and can be relied on to produce only female plants. By creatively applying technologies to seed feminization, modern breeders like Kannabia can ensure female genetics in seeds with a nearly 100% success rate.
Colloidal silver is by far the easiest to source or make. It is non-toxic, non-caustic, and can be bought from a pharmacy or easily online. The other solutions can be dangerous, difficult to get a hold of, and expensive—except gibberellic acid, which can be found in nurseries, but is not as effective as colloidal silver. But if you want to watch some freaky plant growth just for the fun of it, give gibberellic acid a try. It is a growth stimulant and makes plants stretch and stretch.
Growing cannabis is all about resinous flowers, trichomes, and rich cannabinoid profiles. These splendid characteristics can only be found on the female flowers. Having gardens full of robust, un-pollinated sinsemilla females means jars full of mind and body-friendly, crusty nuggets.
TECHNIQUE 1: COLLOIDAL SILVER
Plants bred using feminization are homozygous. This can have two effects that can’t be assessed until the seeds are grown. Homozygosity will increase the dominant or recessive traits of the parent in the progeny, so features you don’t want and do want can be amplified. Genetics is a weird, weird thing.
Spray the plants to be feminized with colloidal silver every day, and three times a day if you can manage. Soak them well. Do this for two weeks, then leave the plants to grow as normal. Some growers report getting results after spraying for only 5–10 days.
Be sure the strength is at least 15ppm, preferably 30ppm. Less than 15ppm produces male sacs with little viable pollen.