Its brown when you mix it, doesnt seem to leave a residue but does smell. Have not applied it during full bloom just before it actually. Personally I would focus on wetting leaves and stems and avoiding the buds where reasonable. The bacteria will in theory spread anyway and it only takes one bite of an inoculated area to infect the pest.
I’ve applied other stuff during full bloom though like pyrethrins and soaps and not had any issue with crisping or burning.
Of course can always test some lowers first.
Also, you should be spraying that stuff on all your other plants like ornamentals and deciduous trees.