Morning 420Blunts.
No! No chemicals on flowering buds, ya can`t get it off properly and you`ll wind up smoking it,,,eeewww.
How tall are your plants?
If you can get a plastic bag over em and tie it at the bottom, you can use some CO2 cartrigdes to kill the mites plus it`s an added bonus for the plants.
Just put plastic bag over plant so you can tie it at the bottom stem, you can get CO2 for pellet guns at MalWart I imagine and just pop the seal on a cartridge or 2 and put in bag with plant and tie off at the bottom.
Mites should be all dead in 24 hrs, and your plant will love you for it.
Hope this helps you some.
ccb