Cultural control of powdery mildew

There are numerous ways to prevent or control powdery mildew on plants:

- Rake up and destroy infected leaves in autumn. Do not add these leaves to compost heaps and bins.

- Remove heavily infected stems or shoots.

- Use disease-resistant species and cultivars. Seed produces often note which plants are mildew-resistant.

- Make sure plants are getting the recommended amount of sunlight. For plants that can be grown in full sun or partial shade, plant in full sun whenever possible. 

- Except for drought tolerant plants, water regularly in dry periods.

- Avoid overhead watering in early morning or in the evening.

- Provide good air circulation within and around plants. Avoid dense planting and prune shrubs to encourage a more open branch structure.

- Apply fertilisers at the recommended rate and frequency. Lush growth from overfertilisation is more susceptible to mildew infections.