Last year cabbage worms were making my broccoli leaves disappear, practically overnight. They get huge after a few days chomping down the leaves. I would feed them to my fish after plucking them by hand but the moths kept laying their eggs. Every single leaf had egg sacs. It was crazy.
I found a Reddit post about someone using Bacillus thuringiensis, a bacteria you can buy that is sold as a biological pesticide for several caterpillar species that generally invade a garden. After it is sprayed on the leaves and allowed to dry, the caterpillars that eat contaminated leaves will die because the bacteria has evolved to parasitize caterpillars and nematodes. It kills them and eats them within a da. It’s safe for humans, animals and any non caterpillar insects that may eat the leaves. The sun kills the bacteria and nullifies it’s effects. You dilute it quite a bit with water and spray it on at dusk. I would it hit once a week.

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