How to use our STS Spray (Silver Thiosulfate)

Instructions for Using Ready-to-Spray STS Reversal Spray

Personal Protective Equipment (PPE):


Wear gloves, goggles and long sleeves and pants.
Consider wearing a protective suit if extensive spraying is planned.

       Step 1: Preparation

      1. Cover any surfaces that you don't want to get sprayed with plastic or a drop cloth to prevent accidental contamination. Keep in mind that STS may stain surfaces, so take appropriate precautions.

      2. Turn off the grow lights or remove the plant from the intense lighting needed for growing. Light breaks down STS Spray. Regular household lighting is fine during spraying, but afterward, the plants must be placed in the dark.

      Step 2: Application

      1. Hold the spray bottle approximately 6-10 inches away from the plants.

      2. Evenly spray the entire surface of the plants, making sure to cover both the upper and lower sides of the leaves as well as the stalk and branches.

      3. Be careful not to get any STS in the root zone. It is best to cover the top of your media to prevent drops from getting into the root zone.

      4. Once the entire surface of the plant is saturated, place the remaining solution back into the light-proof bag and store it in the fridge to ensure freshness. The spray expires in 3 months when kept in the fridge.

      Step 3: Timing and Frequency

      1. STS can be applied successfully in many different ways. We have found it's best to start spraying 12 days before flip with photoperiod plants. With non-photoperiod plants, it's best to start spraying on day 17 or when the first white hairs appear, whichever comes first.

      2. Spray your plants every three days, right before lights out as described in the application section.

      3. Some plants will reverse fully being sprayed every 5 days, while the occasional strain will require daily spraying. It depends on genetics. We have found every 3 days has the highest success rate and yeilds the most pollen while not overdoing it.

      Step 4: Post-Application Care:

      1. After applying the STS reversal spray, allow the plants to dry completely in a room without fans blowing directly on them. Minimal air movement is important until the plants absorb the STS.

      2. Move the plants to a dark place with no light at all. They must stay in the dark for 6 hours for the STS to properly block ethylene production, yes even the non-photoperiod.

      3. Once the plants are completely dry, you can turn your fans on. This may take less than 6 hours. Try to avoid turning on the lights, and if necessary, use a flashlight while turning on fans in the dark area

      Step 5: Storage:

      1. The refrigerator is the best place to keep your spray and will ensure it stays potent for at least three months.

      2. The product can be frozen for up to 9 months. When freezing, pour out a small amount of the solution from the bottle first or use some of it before freezing to prevent the bottle from cracking. Only freeze once; our studies have found that no noticeable degradation occurs with a single freeze, but multiple or consistent freezing between uses can cause degradation.

      Step 6: Collecting and Drying Pollen:

      1. Once your plants have reached the appropriate stage and the pollen sacs have developed, it's time to collect the pollen for use in breeding or other purposes.

      2. To collect pollen, gently shake or tap the mature pollen sacs over a clean surface or container to release the pollen grains.

      3. Use a fine scraping tool to carefully gather the pollen grains and transfer them to a clean, dry container for storage.

      4. Allow the collected pollen to air dry in a well-ventilated area at room temperature (around 20-25°C or 68-77°F).

      5. Stir or gently agitate the pollen occasionally during the drying process to ensure even drying and prevent clumping.

      6. Use a humidity gauge to monitor the relative humidity levels during drying. Ideally, the humidity should be maintained between 30% and 40% to prevent mold growth and ensure proper drying.

      7. Once the pollen has dried completely, transfer it to a clean, dry container for long-term storage.

      8. Store the dried pollen in a cool, dark place away from moisture to maintain its potency and viability.

      9. Label the container clearly with the date of collection and the strain of plant from which the pollen was collected for easy identification and tracking.

      10. Use the dried pollen within a reasonable timeframe to ensure its effectiveness in pollinating female plants or for other intended purposes.