Cut or burn then coat entire plant in serenade you mix it in a pump sprayer it raises the pH on the leaves so mold can't form also tying down branches or anything else to increase air flow along with shaking the extra moisture off in the morning keep an eye on your plants if caught early its easy to deal with. But fire is the only thing that kills it! So your best option is preventing it buy some serenade or you will be fucked if its only the 3rd week!