What is it?
Powdery Mildew is a fungal disease of trees, shrub and grass. It thrives in shade and humid condition, where spores can be spread by rain and wind in warm and humid weather.
Symptoms
- A white/grey powdery coat on leaf surface, stem or buds.
- Young leaves, water sprouts are often affected severely.
- Infected leaves may be twisted.
Damages
- Leaves turn yellow and drop prematurely in severe infestation.
- It rarely kill the plants, but it will weaken the host.
What to do?
- Rake and remove all fallen leaves to reduce spreading in the following spring.
- In dormant seasons, prune the tree to increase light penetration and air movement to the tree.
- In growing seasons, avoid excessive pruning and only remove severely infected shoots and dead branches to reduce chance of infection.
- Chemical control is usually not required.
- Apply fungicides if infection is severe.
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