STS Concentrations

Advanced Techniques
1

Hi all,

Reading about recipes for STS I noticed there are different concetrations for the different components.

Thinking on Franco’s work for GHS to reverse Exodus cut. He mentioned 150 experiments over 9 months.

Wondering if the success was due to concentration formulas or not. Also wondering if you have any tip, trick or some experiment comparison to show.

Any advise much appreciated

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STS Concentrations and alternative methods.

[…] Furthermore, none of the plants treated with the STS solution under the methods (spray or micro drip) at the evaluated concentrations expressed male flowers in female cannabis plants effectively. Contrary to that reported by Mohan Ram and Sett (1982a) and Sarath and Mohan Ram (1979), who indicate that the use of 100 µg of the silver ion (AgNO3) and 50 µg of the STS compound (Ag(S2O3)) was sufficient to reverse more than 80% of the flowers in 100% of treated female Cannabis plants. In addition, Lubell and Brand (2018) state that 3 mM of STS induces between 75 and 100% of the production of male flowers in female cannabis plants. Despite the non-inductive effect of STS for sexual reversion observed in this work, it should be noted that STS is the most used method by cannabis growers to induce the production of male flowers in feminized plants.[…]

From “Sex reversal in female cannabis plants as a in response to male flowering promoters”

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My recipe from my chemist which I copy as I received it.

How to make one 300ml bottle of STS:

-Put on laboratory grade safety goggles. If you do not have laboratory grade safety goggles do not proceed. Fill plastic bottle with 300ml of DISTILLED water. Add 0.030 grams of Ag-N-O3 to the 300ml solution of DISTILLED water. Give it a good stir while wearing your goggles until dissolved. Next add 0.180 grams of sodium thiosulfate pentahydrate to the 300ml DISTILLED water containing the dissolved sodium thiosulfate pentahydrate. Give it a good stir until everything has dissolved.

-DO NOT REMOVE YOUR SAFETY GOOGLES UNTILL YOU HAVE PUT AWAY YOUR STS SOLUITON AND WASHED YOUR HANDS THUROUGHLY WITH SOAP AND WARM WATER!!!

By the chemist!

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I use Pentahydrate. I’ll share my recipe for almost 500 ml of sts. Good for making new fresh batches often while allowing me to spray many plants per bottle.

Base Solutions
Part A 500ml distilled water to 0.5 grams silver nitrate, swirl or stir until dissolved.

Part B 500 ml distilled water to 3.9 grams of Sodium Thiosulfate Pentahydrate, gently shake until dissolved.

Base solutions stay in a cool dark place.

One Jar of 400 ml of distilled water.

Sts Spray steps

  1. Add 40 ml of Part B to an empty clean jar.
  2. Add 40 ml of Part A to a separate empty clean jar.
  3. Stir/swirl Part B jar to create a vortex.
  4. Pour Part A contents to your Part B Jar before the vortex stops.
  5. Pour the A/B solution into spray bottle.
  6. Pour 400 ml of distilled water into sprayer.
  7. Cap sprayer then swirl contents around in sprayer.
  8. Spray stems and nodes only once every three days.
  9. Store in cool dark place, replace with fresh sts every two weeks.
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Firstly questioning now if STS is the best/only way to reverse famale sex, and the answer is probably no.

Nevertheless STS is an option working very efficiently.
I found this research article comparing STS Concentrations, applications, etc on 3 strains.

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