How to rid azaleas of a gray/blue fungus that appears to killing them?
Fungus/Lichen on Azaleas
Certified GKH Gardening Expert
The fungus is lichen and is not what is killing the plant. Lichen is especially attracted to plants that are unhealthy, so it is a symptom rather than a cause of the plants dying. What other symptoms do the plants have? We can identify what is killing the plant if we know that. This article will also give you some ideas: https://www.gardeningknowhow.com/ornamental/shrubs/azalea/common-azalea-problems.htm