Oh dear, presumably you mean you sprayed the plants. Nothing much you can do - usually the best course is to wash off immediately, but if it was yesterday, depending on the weedkiller you used, it's probably too late.

Not a lot you can do now as Bamboo says. It is also not a good idea to use bug killer on your food crops as it acts as a systemic and remains in the plant so you end up eating the toxins. Bug killers also kill off all the good bugs as well as the 'bad' ones.

Most weedkiller says "Don't use within 6 hours of rain" which I've taken as "You've got 6 hours to wash this off if you spray the wrong plants", but the quicker the better for getting it off. I agree that "yesterday" is probably too long ago, but you've got nothing to lose by trying! Try washing the leaves, stems etc and wait and see.