Great advice, BigD! Safer® also makes a BT concentrate-little tiny bottle,but it makes like 10 gallons of spray,and you can spray every day if you want to, right up to harvest.
I had an outdoor Cheese last year that the caterpillars got to (Until I started spraying with BT)
I just dug the dead stuff (and the caterpillar
) out, and left the rest of the bud to finish- by harvest time,
those buds were just as big and healthy as the untouched ones.
After digging the dead stuff out, I also gave the affected buds a couple of blasts with straight (3%) peroxide to kill any uglies that might be lurking in there.
If you found one caterpillar, there's probably more- look all the buds over closely- if you see
any brown or tan spots on them, you need to dig into that bud, or at least spread it open a little to check for the little buggers- if you find one, pull it out with tweezers, and shoot a little peroxide into that bud where the caterpillar was- it won't hurt the bud, but it'll stop any rot that may be starting in there.