Powdery mildew

How to treat?

• Biological

  • Wash the spores from a susceptible plant with a stream of water.

  • If possible remove and destroy the infected parts of the plant. Remove infected parts during the vegetative growth period and infected buds during the vegetative dormancy.

  • Apply ecological products for plant protection (e.g. potassium bicarbonate, neem oil, baking soda).

  • Introduce natural enemies - predators, parasites, or diseases (e.g. bacteria Bacillus amyloliquefaciens, Bacillus pumilus).

• Chemical

  • If necessary, apply a fungicide. Powdery mildew on deciduous trees usually does little damage, so chemical control is not needed.

  • If necessary, apply fungicide containing penthiopyrad (GHS09: Environmental hazard) on apple trees and pear trees.

  • If necessary, apply fungicide containing tebuconazole (GHS07: Harmful, GHS08: Health hazard, GHS09: Environmental hazard) (on ornamentals).

• Disease prevention

  • Grow the plants in sunny places with good air ventilation.

  • Improve the air circulation around the plant (e.g. by pruning excess foliage or increasing the spacing between plants).

  • Avoid excess nitrogen fertilization.

  • Avoid prolonged wetting of the leaves, which can be caused e.g. by overhead irrigation.

  • Use resistant species and cultivars as well as healthy, certified seeds and seedlings.