Might be aphids. I have trouble with them myself this time of year. Ladybugs help. You can order live ladybugs online cheap(1500 for $6.50 u.s.). 1500 will take care of 500 sq. ft. of plant space.

A photograph of the problem would help - aphids don't eat leaves, they penetrate the sap stream and suck that, usually underneath the leaves or on the young stems. Leafcutter bees and other similar insects take even, usually curved, pieces from the edges of leaves, but other than that, more info is needed - like a photo.