Preparation of STS:
First, a stock solution is made. It consists of two parts (A and B) that are initially mixed separately, then blended together. Part A is ALWAYS mixed into part B while stirring rapidly. Use distilled water; tap water may cause precipitates to form.
Wear gloves while mixing and using these chemicals, and mix and use in a properly ventilated area. A mask will prevent the breathing of any dust, which is caustic. STS is colorless and odorless, and poses minimal health risks if used as described here. (See material safety data sheet links below). Note that silver nitrate and STS can cause brown stains upon drying, so spray over newspaper and avoid spilling.
Part A: .5 gram silver nitrate stirred into 500ml distilled water
Part B: 2.5 grams sodium thiosulfate (anhydrous) stirred into 500ml distilled water
The silver nitrate dissolves within 15 seconds. The sodium thiosulfate takes 30-45 seconds to dissolve.
The silver nitrate solution (A) is then mixed into the sodium thiosulfate solution (B) while stirring rapidly. The resulting blend is stock silver thiosulfate solution (STS).
This stock solution is then diluted at a ratio of 1:9 to make a working solution. For example, 100ml of stock STS is added to 900ml of distilled water. This is then sprayed on select female plants.
Both the stock STS and the working solution should be refrigerated after use, as well as the powdered chemicals, to avoid activity loss. Excess working solution can be safely poured down the drain after use (with ample running water) with negligible environmental impact. It’s pretty cheap.
Each liter of stock STS will make ten 1-liter batches of working solution of STS. With the minimum amount of base chemicals ordered from Photographer’s Formulary (see link below), this means that each 1-liter bottle of working solution STS costs less than 9 cents, and can treat 15-20 mid-sized plants. That’s 200 1-liter batches of STS for $18. Note that the distilled water costs far more than the chemicals.
These protocols are, to the best of my knowledge, the best practices. Others do it differently so do your homework
1) Start spraying the plant to be reversed (and flip it) 2-3 weeks BEFORE you flip the females
2) Spray every day, focusing on the nodes
3) At around 4.5 weeks after you first started spraying, if the pollen isn't actually dropping from the reversed plant, you'll want to harvest all of the flowering buds and let them dry in a trim bin with a screen to collect pollen (they sell them in most grow shops)
4) Once the buds are dry you'll want to grind them up and collect the pollen.
I'm sharing this with you because sometimes it takes a lot of work to collect some pollen, but if you don't do this work you might end up with nothing.
Pollen should be applied to female plants at between 3-4 weeks of flowering for most, a little later for Sativas.
First, a stock solution is made. It consists of two parts (A and B) that are initially mixed separately, then blended together. Part A is ALWAYS mixed into part B while stirring rapidly. Use distilled water; tap water may cause precipitates to form.
Wear gloves while mixing and using these chemicals, and mix and use in a properly ventilated area. A mask will prevent the breathing of any dust, which is caustic. STS is colorless and odorless, and poses minimal health risks if used as described here. (See material safety data sheet links below). Note that silver nitrate and STS can cause brown stains upon drying, so spray over newspaper and avoid spilling.
Part A: .5 gram silver nitrate stirred into 500ml distilled water
Part B: 2.5 grams sodium thiosulfate (anhydrous) stirred into 500ml distilled water
The silver nitrate dissolves within 15 seconds. The sodium thiosulfate takes 30-45 seconds to dissolve.
The silver nitrate solution (A) is then mixed into the sodium thiosulfate solution (B) while stirring rapidly. The resulting blend is stock silver thiosulfate solution (STS).
This stock solution is then diluted at a ratio of 1:9 to make a working solution. For example, 100ml of stock STS is added to 900ml of distilled water. This is then sprayed on select female plants.
Both the stock STS and the working solution should be refrigerated after use, as well as the powdered chemicals, to avoid activity loss. Excess working solution can be safely poured down the drain after use (with ample running water) with negligible environmental impact. It’s pretty cheap.
Each liter of stock STS will make ten 1-liter batches of working solution of STS. With the minimum amount of base chemicals ordered from Photographer’s Formulary (see link below), this means that each 1-liter bottle of working solution STS costs less than 9 cents, and can treat 15-20 mid-sized plants. That’s 200 1-liter batches of STS for $18. Note that the distilled water costs far more than the chemicals.
These protocols are, to the best of my knowledge, the best practices. Others do it differently so do your homework
1) Start spraying the plant to be reversed (and flip it) 2-3 weeks BEFORE you flip the females
2) Spray every day, focusing on the nodes
3) At around 4.5 weeks after you first started spraying, if the pollen isn't actually dropping from the reversed plant, you'll want to harvest all of the flowering buds and let them dry in a trim bin with a screen to collect pollen (they sell them in most grow shops)
4) Once the buds are dry you'll want to grind them up and collect the pollen.
I'm sharing this with you because sometimes it takes a lot of work to collect some pollen, but if you don't do this work you might end up with nothing.
Pollen should be applied to female plants at between 3-4 weeks of flowering for most, a little later for Sativas.
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