Welcome Kevin! I’m in northeast Ohio near Youngstown and grow peaches, plums, cherries, grapes, apples, etc… I use dormant copper early winter and late winter, then try to follow Alan’s low spray schedule Spray Schedule- Synthetic Materials . I think the dormant copper is a good safeguard against peach leaf curl. I usually use daconil instead of immunox before fruit forms. I think it helps with black knot on Euro plums, which I originally had quite a problem with. After fruit forms I use Immunox, which seems very safe. This year I bought the bonide spray with captan and malathion but if I remember correctly the captan might do cosmetic damage to plum leaves so I’ll just use it on cherries, grapes and peaches and use the Immunox on plums. I have a few 5 year old trees and lots of three year old trees. If everything holds this year I’ll have my best fruit set on three year old Castleton plums, President plums, many kinds of tart cherries and most of my peaches.