how to make wettable solvent blog banner

Make Your Own Wettable Solvent

Wettable sulfur is a common preventative and curative treatment for powdery mildew, mites, rust, and black spot—including on cannabis. The product you’re holding (Safer’s Sulphur Dust) is 92% sulfur and labeled for vegetables, fruits, and flowers, making it suitable for use on cannabis during the vegetative stage.

  • HOW TO MAKE MAKE WETTABLE SULFUR SPRAY

    Since sulfur dust isn’t water-soluble on its own, it must be finely mixed and agitated in water. A typical concentration for foliar use: Mix 1 tablespoon (approx. 10g) of sulfur dust per 1 gallon of water Use warm water and shake/stir thoroughly to keep the mixture suspended Optional: Add a few drops of unscented liquid soap or horticultural surfactant to help it stick to leaves

  • WHEN TO SPRAY

    Use only during the vegetative stage 🚫 Stop at least 2–3 weeks before flowering begins Apply in the early morning or late evening to avoid sunburn and leaf damage Spray weekly as a preventative, or every 5–7 days if pests/mildew are present

  • HOW TO APPLY

    Use a clean handheld or pump sprayer Spray leaves evenly—top and underside until lightly coated (avoid dripping wet) Avoid spraying in high heat (over 26°C / 78°F) or intense sunlight Do not mix with oils (like neem)—allow at least 2 weeks between sulfur and oil applications to prevent phytotoxicity (burn)

  • REMINDERS

    Always test on a small section of the plant first Do not inhale dust or spray mist Wear gloves and a mask when mixing and spraying Keep out of reach of pets and children

top