It will be hard to come up with a cure without knowing what is eating your plants. Look on the bottom side of the leaves for things like caterpillars, aphids (might be translucent green and hard to spot), or other insects. I have holes under the leaves of several of mine and had to check half a dozen leaves before I found a couple tiny caterpillars having dinner.
I have had some luck with pepper sprays but it is tedious to get the spray up under the leaves. It also helps deter larger animals (rabbits, groundhogs). You can also try neem oil. But again finding the culprit will help you pick what you need to control it.