It was recommended to me to try sprinkling corn meal around the bushes once a month and to spray a milk/water solution on them to prevent Cercospora Leaf Spot. Does anyone know if this will work? I once heard this suggested for use against Black Spot, but different fungus don't always react the same to one single all-purpose kind of treatment & so I wondered about the effectiveness of this. I do all the recommended things like clean up, good air flow, etc. and it's still a problem.