The cure for PM is to innoculate the plant internally with a lactic acid mix or high sulfur compound.

There are inherent problems with this, as once you spy PM the simple fact is it's contaminated your crop. At this point the only chance you have is heavy chemical (and subsequent flushings) of sulfur and magnesium in an attempt to control and kill it from over-nutrition (which the plant should withstand.) This will affect the taste of your crop if you are not careful in managing the dosage.

Sadly, it is very difficult to control taste and potency when you get PM infestations.