Can Sulfur Spray Be Used on Peach Trees?
Sulfur spray is made by diluting wettable powdered sulfur, micronized sulfur or liquid sulfur concentrate with water. It is an effective organic pesticide that controls insects and fungal diseases on various fruit and vegetable plants and trees, including peaches. Mites, brown rot, powdery mildew and rust are among the pests and diseases for which sulfur spray is effective on peaches.
The University of California Statewide Integrated Pest Management Program recommends wettable sulfur spray for control of the peach silver mite. Micronized sulfur spray is effective against red spider mites. Use the sprays at regular intervals starting at the budding stage and ending at harvest.
Fungal Disease Control
All forms of sulfur spray are effective against powdery mildew, brown rot at the fruit or blossom stage, scab and rust. Micronized sulfur is effective against leaf spot as well. Mix the spray according to the label and apply it at all stages of the growing process at intervals of 10 to 14 days between applications.
Manufacturers of micronized and wettable sulfur recommend their products for shothole disease, or coryneum blight. However, the University of California Statewide Integrated Pest Management Program ranks it as one of the least effective pesticides for this purpose. If the telltale small brown spots of shothole disease appear on fruits or twigs of peach trees you are treating with sulfur spray, you may need to use a stronger pesticide to control this disease.
Notes and Precautions
Sulfur spray cannot be used with oil sprays. It also causes plant damage when sprayed at high temperatures, and some crops, including apricots, cucumbers, walnuts and Anjou and Cornice pears, are particularly sensitive to sulfur. Do not allow spray drift to contaminate sensitive plants. As with all pesticides, mix sulfur spray according to label directions, and wear rubber gloves and eye protection when mixing or spraying sulfur pesticides.
- Bonide Sulfur Plant Fungicide: Product Label
- Plant Health Technologies: SuperSix Liquid Sulfur: Product Label
- UC-IPM Onlline: UC Pest Management Guidelines: Peach Silver Mite
- UC-IPM Onlline: UC Pest Management Guidelines: 2012 Fungicide Efficacy and Treatment Timing
- UC-IPM Onlline: UC Pest Management Guidelines: General Properties of Fungicides Used in Peaches
- UC-IPM Onlline: UC Pest Management Guidelines: Shot Hole Disease
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.