How to use acephate on S/H orchids?

[Kim in CT]

I'm looking for How-To info on using "big guns" insecticides acephate, imidacloprid) with orchids in S/H. I've picked up a few mealy bugs that I am spot-treating with Q-tips and alcohol, and I would rather not use those other poisons, but if I had to go that route how would I do it? My orchids are about to go outside for the summer and I anticipate they will pick up some hitch-hikers before I bring them back inside. Thanks!