My azaleas have this condition also and this year is the worst ever, probably
because of the moisture. Some years, the condition disappears even though I
never spray fungicides. Here's an explanation:
Anne Lurie wrote:
Some of my azaleas have weird greenish-white things on the leaves -- the
plants look as though garden gnomes came in & stuck popcorn on the leaves!
These things are on the underside of a leaf, and there's a hole where
something apparently chewed its way out, if that makes any sense.
What should I do now? Should I spray the plants with pesticide? If these
things were caterpillar chrysalises(?), the caterpillars are gone.
So far, only my older azaleas seem to have this problem, but I'd obviously
like for it not to spread to the dozens of newer azaleas I've planted in the
last few years.