This disease is not only unsightly, but reduces the ability of azaleas to produce flowers in future seasons.
Infected leaves become fleshy and severely distorted.
As the galls form, affected parts may become whitish or light green. Sometimes a fleshy rosette of leaves appears at the tip of a branch, or a gall becomes bladder-like as it decays and dries out. Azaleas are most susceptible to infection by the leaf gall fungus when young leaves appear following bloom. At this time, fungus spores land on young leaves and stems, germinate, and infect these plant parts during rainy weather. Infection cycles occur as long as young leaves are present on plants.