One of the most annoying critters we fight in the cool weather is the Cabbage Looper. A green inch worm looking bug that loves leafy plants. They can be very damaging but they are also easy to control. You need to inspect the garden to identify the problem before they get out of hand. The farmers call this crop inspection, scouting. My weapon of choice is Bt (Bacillus thuringiensis). Bt is available in both liquid and powder called Dipel Dust. The liquid should be used with a sticking agent like liquid molasses. The only issue with liquid molasses is that I have had it gum up the sprayer. You don’t have to deal with that if you use the powder but it is very hard to get it to stick to the bottom of a leaf.