Can you post a pic?
You sometimes need to get down to the plants level and search carefully for insects on the plants.
I don't know what your tolerances are for pesticides, but you can use some Diatomaceous Earth to discourage insects. It is not a chemical.
There are some other herbal remedies that sometimes work. It would help if you could find the culprit.
Any grasshoppers around?
Gardening at 5000 feet elevation, zone 4/5 Northern Utah, Frost free from May 25 to September 8 +/-