Apple scab is a very common occurrence on crabapples and fruit trees. It is a fungus causes black spots on the leaves and is a preventable disease.
In fact, it can typically be controlled with regular applications of Citrus, Fruit, Nut and Orchard Spray by Bonide.
Read more about Apple Scab and how to prevent it below.
Apple scab is caused by the fungus Venturia inaequalis and shows up on the foliage of plants in the form of round, brown to green, velvety spots. This disease will. not kill the plant but it can cause the leaves to go brown and curly.
What causes Apple Scab?
This fungus shows up most frequently during season of damp, cool weather. The fungal spores are often released during periods of rain. In our area, it will begin during spring and then we often see a re-occurence over the summer.
How to Prevent Apple Scab
There is no way to totally prevent Apple Scab. However, it is easily managed.
Best Products to Treat Apple Scab
We recommend regular applications of Citrus, Fruit, Nut and Orchard Spray by Bonide. Ideally, an early season application will help prevent the occurrence of apple scab. This product can be applied as soon as outdoor temperatures reach around 40 degrees and is an all around product for protecting plants against insects and disease. We do not recommend applying this product while your trees are flowering.
For more information on apple scab, read this article from The Morton Arboretum.
Want to read more about how to grow an orchard? Here are a couple other recent articles.