Strawberry plants can grow in the wild or can be cultivated by the home gardener. Easily grown in garden beds and in containers, strawberry plants can provide a tasty early summer treat. While strawberry plants are particularly attractive to certain types of predators and pests, they are also susceptible to infections and disease. A white powder on the leaf of the strawberry plant indicates that it has been affected by powdery mildew.
About Powdery Mildew
Powdery mildew is a type of fungal infection that can affect a large number of plants, including tomatoes and cucumber plants. Powdery mildew most often affects the lower leaves of the strawberry plant, but it can appear on any portion of the plant. Powdery mildew can spread after the initial infection. It prefers moist, wet and cool conditions.
Powdery mildew is one of the easiest infections to recognise. It creates a thin layer of white powder on the top or bottom portions of the leaf. If left untreated, powdery mildew will affect as many portions of the above-ground plant as possible. Over time, the plant leaves will become distorted and wither away. Powdery mildew begins as small circles of white or greyish powder, and then spreads.
Powdery mildew can be controlled using chemical or natural fungicides. Options include neem oil, potassium bicarbonate or sulphur. Large infections of powdery mildew are best treated using a spray. However, if only a small portion of the plant is infected, or it is an early infection, consider cutting off the infected portion of the plant to help prevent the spread of the fungus. Do not compost the infected portion of the plant.
Cultural controls are the easiest way of preventing powdery mildew infections. Powdery mildew prefers cool, humid and wet conditions, so mulching your plants will help keep the leaves of the strawberry out of the wet soil. Plant your strawberries in a sunny rather than shady location, and mix in compost prior to planting to encourage a well-draining soil. Purchase a breed of strawberry plant that has been bred to be resistant to powdery mildew.
- Colorado State Univeristy; Powdery Mildew; B. Edmunds and L. Pottoroff; 2009
- University of California IPM Online: Powdery Mildew on Ornamentals
- Virginia State University; Powdery Mildew of Cucurbits; Mary Ann Hansen
- Ontario Ministry of Agriculture, Food and Rural Affairs: Powdery Mildew
- University of Florida; Powdery Mildew of Strawberries; N.A. Peres and J.C. Mertely; 2009
- Purdue University; Growing Strawberries; Bruce Bordelon; 2001