Asked July 22, 2021, 10:16 AM EDT
Chittenden County Vermont
Cabbage worms are common in the brassica family including kale. Is is likely that there are eggs in the soil that will become larvae/caterpillars and then turn into white moths. The cycle continues. Use a product called BT (bacillus thuringiensis) - I prefer the liquid mixed with water in a sprayer and spray the undersides of the leaves. This needs to be applied regularly as directed.
If the flying insects you see are white, they are white flies, but they are not making the holes. If the insects are actually jumping and black, those are flea beetles. Yes, they make small holes in kale. Here is how to control them: http://extension.umd.edu/growit/insects/flea-beetle
Bt will work well to control all of the caterpillar species when they are young caterpillars. It becomes less effective as they near full-size. https://extension.umd.edu/hgic/topics/cabbage-looper-vegetables
I cut and pasted a bunch of links from educational website, and I apologize that it is so scattered. I hope some of this information helps to protect your next kale crop.