Catapillers? cabbage worms? wicked little fuckers

I had them bad last year but went and bought some SAFERS catipillar killer with bt.its gota have the bt its what kills em.double the mix rate and the plants love it and the fukers will b gone n 4 days.repeat after 5 days

Hi, i'm about a month & a half into flowering and now a couple of my babies have caterpillars, they are muching away the tops of some of the colas :mad: the buggers are relatively small and hard to spot, but the evidence is there, some of the top are brown. I have found about a half dozen and picked them off by hand, but can anyone tell me of a good Pyrethrum insecticide spray that is safe to use.