When procuring feminized CBD hemp seeds, you may wonder how the plants become feminized and you can be guaranteed a certain percent are female. There are a few ways that growers achieve this, and that is through a Silver Thiosulfate Solution, Colloidal Silver, or Rodelization.
STS (Silver Thiosulfate Solution)
Silver Thiosulfate Solution is a fairly easy to create solution which reverses a female cannabis/hemp plant to produce stable feminized pollen. The solution is a mix of silver nitrate, sodium thiosulfate, and other ingredients.
While the solution can be used to reverse female plants, it does not eliminate hermaphroditic plants. If a reversed female plant is exposed to stress, such as with light leaks, the plant will create both feminized and hermaphroditic pollen, which will then produce both female and hermaphroditic seeds. The same is true for any plant with hermaphroditic triggers that flowers in a space that has those triggers.
Growers who use STS are unable to tell which flowers produce hermaphroditic pollen and which are producing feminized pollen as the flowers look the same. In addition, plants that have been sprayed with STS are not safe for human use or consumption (although the seeds are).
Colloidal Silver is a mixture of silver particles and distilled water that causes hemp/cannabis to display male characteristics when sprayed on. This method allows a grower to produce feminized seeds using any two female cannabis plants and allows the grower to produce seeds consistently.
When a female cannabis plant enters the flowering stage, it must be thoroughly misted with colloidal silver every day. The plant will begin producing male “balls” full of pollen. The plants must be misted every day until the male pollen sacs form, which usually takes about 10-14 days.
Unlike STS and the Collodial Silver methods above, Rodelization is completely natural and is considered the simplest method to create feminized seeds. However, Rodelization is often unreliable and may not produce much pollen.
The premise of Rodelization is that some female cannabis/hemp plants will start growing male pollen sacs if they’ve been left in flowered too long (past the peak point of harvest). This is considered a last-ditch effect by the plant to pollenate itself so that it produces a few seeds to carry on its genetics.
Growers will collect these male pods and use them to pollinate other female plants, by covering their buds with pollen after they’ve been flowering for 2-3 weeks. Female plants pollinated this way will start growing all-female seeds. Growers can pollinate only some of the buds on a plant to produce seeds and leave the other buds alone so that they may still be consumed.
One common issue with Rodelization is that some strains of plants do not appear to grow male characteristics naturally. In addition, to use this method, growers must select plants that have a natural genetic tendency to show male characteristics. This can produce offspring which are more likely to show male characteristics, and this isn’t desirable if growing for CBD.
Lastly, this method also produces far less pollen than the other two methods listed above. This method, however, is one of the only ones that can be implemented with an organic grow.