Powdery mildew is a prevalent fungal disease which forms a white powdery cover on the apple tree. It flourishes in humid mild conditions (with no rain), especially in shady spots with little air circulation and damp conditions.
Plant Part: Whole tree
Season: Summer - Spring
Symptoms: White powdery coverings on buds, shoots, leaves and fruit. If the buds are affected the leaves may develop abnormally, appear brittle and curled. They may also drop prematurely. On red skinned Apples, symptoms are easy to identify as they develop a pattern of fine, yellowish criss-cross lines.
Prevention: When planting your Apple Fruit Salad Tree, allow for plenty of space around the tree to help create adequate air circulation. Having a good watering routine will help reduce the risk of this disease. Ensure water is delivered to the roots and does not get on the leaves. Using a seaweed/fish based plant tonic once a fortnight can also be helpful.
Control: To control the spread of Powdery Mildew, remove the affected leaves from your tree to stop it spreading. Dispose of any leaves you remove (and any prematurely fallen leaves) in your red bin - not in your compost or green bin. Apply a spray with wettable sulphur (we suggest Manutec, and to follow the directions on the packaging). When applying any sprays/chemicals to your fruit salad tree, do so in the early morning – not in the hot sun! We recommend applying sprays that won’t kill off the good insects like black and yellow ladybirds. Beneficial insects like these two will help control fungal diseases and other nasties in your garden.
References: QLD Department of Agriculture, Fisheries & Forestry, DPI Orchard Plant Protection Guide 2020, and our FST team
