If you start seeing holes in your cabbage-family items (including broccoli, kale, collards, etc), you’ve likely got cabbage worms.

There are a few different types of cabbage worms… cabbage loopers are green, but what I’ve got are cross-stripped cabbage worms. They turn into a brown moth and not the white cabbage butterfly we’ve come to associate with cabbage.
Prevention includes hand picking them off, exclusion using an insect netting, or spraying Bt (an organic bacteria and not harmful not chemicals).
PRODUCTS SUGGESTED IN THIS VIDEO FOR PREVENTION: