How to Feminize Seeds
The cannabis industry has evolved more in the last 15 years than it has in the last century. Society has also evolved, allowing cannabis and the idea of weed to slowly make its way into pop culture, with more and more strains available as well as accessories for smoking or consuming cannabis. Nowadays, pretty much anyone can grow cannabis in their own house with all of the necessary equipment to make their own strains. Years ago only a select few had access to such equipment. Today we’re going to show you how to feminize seeds. You won’t need many items to do so, and the ones you do need are easy enough to get.
Like most living creatures, cannabis plants need a male and a female specimen to reproduce; the male pollinates the female plant which causes seeds to grow. The resulting seeds have genes from both the mother and father plants, so it has a 50% possibility of being female or male. This is why you need to find a way to get your seeds by using just female plants, completely getting rid of male genes, which only leaves the possibility for female seeds.
How to Feminize Seeds | Tutorial
Many growers know that if you stress out cannabis plants, they can easily become hermaphoridtes (a plant with both male and female sex organs) which end up creating male flowers that create pollen which then “impregnates” the plant and others around it. The issue with stress-caused hermaphrodite plants is that most of the resulting seeds tend to be hermaphrodites too, so it’s not the best method to use and it also stresses your plants out quite a lot.
In order to turn a female plant male without stressing it out, all you need is some Silver Thiosulfate, also known as STS. If you apply STS to female plants it will modify their ethylene levels, which is the hormone in charge of determining the sex of certain plants. This causes female plants to change sex and turn into males without the disadvantage of male genes.
Making your own STS only takes about 15 to 20 minutes and you’ll need two ingredients: Sodium Thiosulfate and Silver Nitrate, both of which can easily be found in any pharmacy and on our webstore. Sodium Thiosulfate is a neutral chemical salt that’s used to reduce side-effects in some cancer treatments and can easily be bought without a prescription.
You can acquire silver nitrate on our webstore, although some people prefer to extract it from other products that contain it, such as Argenpal, a product used to get rid of warts – each one of these little contains a very small amount of Silver Nitrate, so it’s probably better just to buy it directly without the need to spend more money or spend forever trying to extract the Silver Nitrate from the product itself. We stock Panreac Silver Nitrate, which may be a bit more expensive but you’re guaranteed the best quality, and it saves quite a lot of time.
How to Feminize Seeds | Making STS
You’ll need protective material such as gloves, safety glasses and a face mask; STS can be quite toxic when inhaled and it can leave large burns on the skin. Make sure you don’t use any metallic objects when making STS – everything should be plastic, as metal can alter the composition and reduce efficiency.
Do not use metal instruments or tools in this process. The first thing you’ll need to do is grab a plastic cup and pour in 20ml of distilled water. Next, depending on your chosen method, get either 7 Argenpal sticks or 0.35g silver nitrate. If working with Argenplal, dilute the tips delicately in the water (the tip is where the silver nitrate is). Grab another plastic cup and add 30ml distilled water and 1.3g of sodium thiosulfate, mixing it slowly until it’s fully dissolved. Then, mix the contents of both glasses and mix slowly again – make sure to use a plastic spoon, no metal.
The result is 50ml of pure Silver Thiosulfate, much too potent to use on your plants, so you’ll need to water it down a bit. Add your Silver Thiosulfate to 400ml of distilled water, so you’ll have around 450ml of STS. Make sure to shake quite a lot until it’s completely mixed. It’s still much too concentrated to apply straight onto your plants; take 100ml of the mixture you just made and add it to 400ml mor of distilled water. You now have 500ml of a usable STS mixture that’s ready to be used on your plants.
For maximum efficiency you’ll need to use it the same day you make it. If stored in a dark, cool space it can last up to 15 days but each day it’ll be a bit less potent. If you have it for over a week and haven’t used it we recommend making another batch if you want the best possible results.
How to Feminize Seeds | How to use STS
STS is used by spraying it on your plants leaves, making sure that it’s entirely covered and dripping. We recommend taking the plant away from your growing area before beginning the process, or the mixture might end up getting on your other plants too. You’ll need to begin applying it 4 or 5 days after flipping the lights, right before your lights go off. This allows you to spray the plant without worrying about the light burning your plants. After 10 days, you need to respray your plants, using the same process, covering the plant in the mixture and letting it soak in in the dark.
The sprayed plant will begin growing male flowers with pollen with can then be used to pollinate whichever plant you want, causing seeds to appear that have absolutely no male genes in them. You can use the pollinated plant in order to make extracts from its resin; the amount of seeds it’ll produce will render it pretty much useless in as far as smokeable flowers. The plant that you’ve applied the STS to will need to be thrown away, as it’s much too toxic to do anything with and if you consume any of it, even its resin, you could run in to some health issues.
When should you polinate your plants?
In order to efficiently pollinate select plants, we recommend having two completely separate grow rooms or areas to work in. One should be for the plants that you’re planning on switching to male in order to obtain female polen; the other should be specifically for the plants that you plan on pollinating once you’ve reverted the other ones.
When using the pollen that you’ve collected from your reverted plants, you need to make sure that the plant that you plan on using it on is fully ready for it; this can depend on the strain you’re growing. The right time to begin applying feminized pollen is actually right when your plants begin to flow real flowers.
You generally want to use the pollen as fresh as possible on a plant that is fully ready to take it on, or else it simply might not work – it’s kind of like people, in that sense. Certain things need to be just right. To harvest large amounts of high quality seeds, you’re probably better off doing a few tests in order to find out when the right moment is. You can do this by testing it out on the same strain before going big.
How to Feminize Seeds | Make your own strains
When making your own seeds you can combine your favorite strains, resulting in a plant that you’ve created yourself that is 100% feminized. When you combine two strains, you’ll get various phenotypes with varying qualities and structures. It’s important that you use regular seeds to do this, as feminized ones are much too weak and might have issues such as stress and end up becoming hermaphrodites.
In order to stabilize the genes in your resulting plants, you’ll need to select the phenotypes you like the most, meaning that you’ll need to grow quite a lot of the seeds that you get from your feminized plant. Then, take a clone from each plant and set them to flower in order to study their characteristics. Once you’re done, you’ll need to pick two mother plants, revert them and cross them with each other to get a more balanced version. This process is repeated as many times as necessary in order to create a balanced strain that has the characteristics you’re looking for.
Feminizing cannabis seeds is quite the process. You need to be able to keep perfect track and control of the timing when it comes to flowering and pollen yield if you want the best possible results. Take your time, do a few controlled tests and then you can start making large amounts of your own seeds.
Learn how to feminize seeds at home. Use silver thiosulphate to make your very own cannabis hybrids with your favorite strains for the best results.
Sts feminized seeds
After much experimentation and recipe adjustments we have finally developed a winning formula for STS plant reversal spray. This spray has been specially formulated for cannabis by the team at Twenty20 Mendocino and is the exact recipe we use to make feminized seeds.
It is important to note that reversing the sex of a female cannabis plant is simple. The difficult aspect is timing the reversal properly and collecting an adequate amount of pollen for the pollination process. We will outline the procedure we follow in order to provide you with as much information as possible to successfully create your own feminized seeds. Please keep on mind that different strains react differently to the spray.
Separate the plants you plan to reverse from the plants you plan to pollinate. The reversal plants will perform best if they are multi-topped plants as apposed to single top plants. It is best to prepare ahead and pinch the tops to facilitate this process.
For abundant seed production you will want a ratio of approximately 1:4 reversed plant to seed mothers. In other words if you have 12 plants to start with you will want to reverse 3 of them. This ratio only applies to commercial seed producers. (see footnote 1)
-You must start the flowering and spray regimen on the chosen reversal plants approximately 21 days before you flower the seed mothers. This timing ensures you get maximum pollen production around the time the female plant is in her reproductive prime. 21 days represents the approximate average used by the team at Twenty20. This can vary between 14 days and 25 days.
-The spraying process begins the day before you switch the reversal plant(s) to flower. This should be done soon after the lights go off or soon after dusk for outdoor plants. Spray the nodal areas, and branches and tops. It is not necessary to spray the entire plant and all of the leaves. A fine mist will do but be sure to get an adequate coating. This process should be completed every 3rd day until the first male pollen sacs begin to open. This is usually around day 20-30. (see Caption 2.)
-At day between day 14 and day 25, start the flowering process on the female seed mother plants. (See footnotes 1)
-After the female plants have a small cluster of stigmas they can be united with the reversed female plants for pollination. We usually do this when the stigmas are protruding but before the calyxes begin to swell.
**Reversed female plants do not produce as much pollen as male plants so it is important to take a few steps to insure proper pollination.
-Always provide adequate airflow to the cultivation area with fans.
-Agitate the reversed plants daily by shaking them gently in front of fans
-Keep the humidity as low as possible; this will increase the amount of airborne pollen. This also helps minimize mold, which can be more prevalent in reversed female flowers.
-If particular reversed plants tend to produce more pollen be sure to shift them around the cultivation area
-You should see signs of successful pollination within a few days of joining the plants. Be patient, the process is much slower and less effective than breeding with males.
Visit our YouTube channel for additional instructions.
Sts feminized seeds After much experimentation and recipe adjustments we have finally developed a winning formula for STS plant reversal spray. This spray has been specially formulated for