white substance on holly leaves

Question

Our holly shrubs have a white substance on leaves, causing them to turn brown and dead looking. Wondering cause and treatment.

Answer 1

Sounds like powdery mildew. This article has information: https://www.gardeningknowhow.com/plant-problems/disease/get-the-cure-for-powdery-mildew.htm
To be absolutely sure, you can take some leaf samples to the local Extension Service for analysis. This link will help you locate the nearest one: https://www.gardeningknowhow.com/extension-search/