Bacillus thuringiensis (Bt), commonly sold in powder under the name Dipel
Dust. You can also buy the liquid form in concentrate. It is an organic
insecticide composed of bacteria that biologically targets chewing larvae or
caterpillars. I only use it when needed because it will kill other
caterpillars if they travel through it. I like the monarch caterpillars on
my dill, fennel and parsley. I have enough to share with them. But the
cabbage loopers that get on broccoli are fair game.

Penny
Zone 7b - North Carolina
"Lily" wrote in message
...
I have green worms on my broccoli. I've been manually removing and
squishing. How can I get rid of them and prevent reinfestation? TIA