powdery mildew or mold

[SoCoMMJ]

This is true, otherwise throw them out. PM will become dormant and come back later, often late in flower when the plant is finishing up.

if it pops up late you can use potassium bicarbonate [Greencure] as a natural defense. I raises the PH on the leaf surface to the point where the PM dies and cant repopulate.
It will darken your pistils if they have not turned yet due to the ph but will kill the PM. Thankfully we have not had to go there for years, but it is a good thing to know. Grape farmers use skim milk at 10:1 [?] as another alternative. [my first reaction there is yuck]