Answer: It's really important to identify exactly what is damaging your plants before attempting to spray something on them. You may do more harm than good. (Also, spraying will kill beneficial insects such as lady beetles and green lacewings as well as the "bad guys.") (Those caterpillars might be butterflies in disguise!) Also, it's best to start with the easiest, most benign method first and if that doesn't work, move on from there. Caterpillars are easy to control by handpicking. Birds will also eat them. Bacillus thuringiensis (BT) is a biological control for them. It's applied to the leaves and after eating them, the caterpillars die in a couple of days. It works only on caterpillars by disrupting their digestive system. Your best bet is to bring any insects (including eggs) in for identification. I hope this info helps.
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