4 lined potato beetle feed on a variety of plants including weeds in the garden. The good news is that they're damage is strictly cosmetic and won't kill the plant. In extreme cases, feeding on new growth will cause the leaves to wilt.

If you choose to use insecticides, insecticidal soap or pyrethrins can be applied to the plants. You'll want to read the label first to confirm they are allowable on edible plants.