Wettable sulfur directions

Updated February 21, 2017

Wettable sulphur is a finely ground yellow powder consisting of 90 to 95 per cent pure elemental sulphur that has been prepared so that it can be dissolved in water. It is used as an insecticide and fungicide for vegetable, fruit, berry and nut crops, as well as for roses. Wettable sulphur can be applied to lawns and outdoor areas to kill chiggers. This product is also used in veterinary medicine to control fleas, ticks and similar parasites in livestock and poultry. When used in home gardens, it is applied either as a spray mixed with water or as a dust.

Fill the sprayer tank with water so that the agitator blades are covered and turn the agitator blades on.

Put on your gloves and add the recommended amount of wettable sulphur to the tank while the agitator blades are running. Use 6 Ibs. per 100 gallons of water for control of mites and fungal diseases on roses and other ornamentals; 0.907kg. per 1000 square feet with sufficient water for coverage to control chiggers in lawns and gardens; or 5.8 to 7.8 Ibs. per 100 gal. of water to prevent mildew on berry crops and grapes.

Fill the tank with water and spray the leaves of the plants with an even, fine mist. Keep the agitator blades on while spraying and wear gloves for safety.

Repeat every five to seven days during growing season.

Wear gloves. Fill a duster to capacity with pure wettable sulphur.

Close your duster cap.

Dust the plants or area you are treating with a fine, even dust according to the recommended coverage for the type of crop you are growing. Use 7.5 to 37.5 Ibs. per acre for control of powdery mildew or leaf spot on peppers; 20 to 40 Ibs. per acre for control of the tomato russet mite on tomatoes; 1.81 to 2.27kg. per acre for control of powdery mildew on peppermint and spearmint; or 10 to 50lbs. per acre for control of powdery mildew on carrots.

Repeat treatment within five to seven days during growing season, except for peppermint and spearmint, which require repeat treatment once every 30 days.


Contact your state agricultural agent to find out exactly how much wettable sulphur to use within the recommended range. Exact amounts depend on local soil and weather conditions, as well as on the severity of plant disease and infestation.


Wash your hands carefully after contact with wettable sulphur. Wash all produce treated with wettable sulphur before eating or cooking. Wettable sulphur is considered an organic pesticide because it is of natural origin, but it is toxic when ingested.

Things You'll Need

  • Tank sprayer with agitator (these can be rented from rental agencies or garden centres)
  • Duster or spreader
  • Rubber chemical-resistant gloves
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About the Author

John DeMerceau is an American expatriate entrepreneur, marketing analyst and Web developer. He now lives and works in southeast Asia, where he creates websites and branding/marketing reports for international clients. DeMerceau graduated from Columbia University with a Bachelor of Arts in history.