Question From: L. Marotta - NEW YORK
Q: My hibiscus plant is three years old and in a pot. I bring it in every winter. This week some of the leaves are shiny and some have a brown powder on them?
My guess is it has powdery mildew. Take photos and a sample leaf to a garden center or nursery that sells these and other tropical plants for an accurate ID and treatment. Low humidity and warm temperatures are conducive to powdery mildew. Best And Happy Yardening, Nancy.