Powdery Mildew Treatment for Plants

Shop powdery mildew treatment products for use on plants and crops listed on each product label. Options may include copper fungicides, horticultural oils, neem-based products, biological fungicides, and other labeled formulations.

Recognize Signs of Powdery Mildew

Powdery mildew fungi can produce white or gray powder-like growth on leaves and stems. Symptoms vary by host, and several unrelated problems can resemble fungal disease. Confirm the signs of powdery mildew and identify the affected plant before choosing a product.

Different powdery mildew fungi have host specificity, so a disease affecting one plant group may not spread to every nearby species. Inspect susceptible plants regularly, including new growth and lower or shaded foliage.

Reduce Conditions That Favor Infection

  • Choose resistant varieties when that information is available.
  • Provide appropriate spacing, airflow, light, irrigation, and fertility to reduce stressed plants.
  • Remove heavily infected leaves when practical without damaging too much plant tissue.
  • Clean tools and manage plant debris according to guidance for the affected crop.

Choosing and Applying a Treatment

Select a product labeled for both the plant and the fungal disease. Preventive timing and early treatment are often more effective than waiting until an infection is widespread, but application intervals and rates vary. Do not assume a universal 14-day schedule or a fixed amount per gallon of water; the current label controls.

Follow label directions for mixing, coverage, personal protective equipment, reentry, preharvest intervals, temperature limits, and compatibility. Homemade baking-soda mixtures are not substitutes for a registered product label.

Compare copper fungicides, broader plant disease controls, and application sprayers.