Measuring and Mixing Stock Solution "A"
- Fill your 500ml measuring cup with 500ml of distilled water
- Measure out .5g of Silver Nitrate
- Mix the silver nitrate powder into the 500ml of distilled water
- Pour the silver nitrate solution into a brown glass bottle and seal tightly
- Label the bottle "A" Silver Nitrate
- Thoroughly clean the 500ml container and rinse with distilled water
Measuring and Mixing Stock Solution "B"
- Fill the 500ml container with 500ml of distilled water
- Measure out 2.5 grams of sodium thiosulfate anhydrous, OR 3.9g of sodium thiosulfate pentahydrate
- Mix the sodium thiosulfate with the 500ml of distilled water
- Pour the sodium thiosulfate solution into a brown glass bottle and seal it tightly
- Label the bottle "B" Sodium Thiosulfate
- Thoroughly clean the 500ml container and rinse with distilled water
Keep Both "A" and "B" Solutions Cool and Dark!
Mixing and Diluting STS
The next step is to mix the two stock solutions together properly, creating the actual Silver Thiosulfate Solution (STS).
Before using the STS, it must be diluted to a weak solution for spraying!
- Measure 50ml of stock solution "B" with the 60cc syringe and gently squirt it in the 500ml glass measure
- Thoroughly rinse the syringe with distilled water, or change to a new syringe
- Measure 50ml of stock solution "A" with the 60cc syringe
- While whisking solution "B" in the glass measure, slowly squirt solution "A" into the glass measure in less than 30 seconds
- Pour the mixed solution into the 32oz brown glass bottle with black sprayer top
- Add 900ml of distilled water to fill the sprayer the rest of the way, leaving room for a little bit of surfactant
- Add yucca extract in small amounts and shake well
- Test spray on a leaf to if solution still beads up and rolls off
- Add additional yucca extract and shake well, until the solution spreads across the leaf instead of beading up
- Thoroughly rinse all tools using more rinse water than usual
You now have a sprayer bottle with a 1:9 dilution of STS and water. You want to do your best to protect it from light and heat. Personally, I wrap the bottle section with a black plastic trash bag and tape it in place. This is for additional light protection while it stores in my fridge. I've successfully used 9 month old solution which was wrapped and stored in my fridge this way.
