Each year, very small, green worms eat all parts of my azaleas when they are in bloom. I have used neem oil but once they are here, it is a little too late as they are voracious! Neem is the strongest chemical I would use in my garden and I worry even it is toxic to the bees.
Certified GKH Gardening Expert
Azalea caterpillar control in the larvae stage relatively easy. However, because the caterpillars feed in groups, they often completely defoliate a portion of a plant before they are discovered. Once the caterpillars are in the adult stage, they can be hand picked and destroyed easily. This is the ideal situation if you have a limited number of azaleas. Most azalea caterpillars can be shaken from the shrub and dumped into soapy water to kill.
Neem-oil is an organic control that must be applied frequently. A second option is to apply Bacillus thuringiensis or BT. BT is a bacterial pathogen widely used as a biological control of pest larvae. It is safe to humans, other animals, and plants when applied according to label instructions.