Many of the leaves on my holly bushes are covered with a grainy black coating. Leaves are dying. How can I treat this?
Black Grainy Substance on Holly Leaves
Certified GKH Gardening Expert
The black substance sounds like a sooty mold issue, most often brought on by pests. Neem oil can also be used to get rid of the pests as well as the fungus. This article will help: https://www.gardeningknowhow.com/plant-problems/disease/how-to-get-rid-of-sooty-mold.htm