Once an infection has been established fungicide sprays are no longer effective. Early in the spring, trees can be sprayed with a fungicide at bud-break and at 2 week intervals throughout the growing season to prevent new infections.
To prevent fungal leaf spots:
- Choose varieties resistant to fungal diseases.
- Remove infected stems and fallen leaves to reduce re-infection in the spring.
- Keep the leaves dry by managing irrigation timing and location.
- If you choose to spray trees with a fungicide, choose a product labeled for leaf spots and always follow label instructions.