Of the 90-100 species of peach trees, the disease causing extreme economic impact is the peach leaf curl. Infection of peach and nectarine leaves occurs annually in the spring before or just after budbreak. Fungal spots are produced in the late spring or early summer and can survive to re-infect the tree during the next year.
Typical symptoms of peach leaf curl are puckered leaves or leaves that appear to be blistered. Affected leaves often turn red or yellow prematurely, and fall prematurely. A white bloom appears, usually on the upper leaf surface, a few weeks after infection.
Disease management using fungicide treatments is most effective during the spring before budbreak. Cool, wet spring conditions favor the development of this disease.
The best treatment, as with many insect and disease problems, is to keep trees healthy to prevent the problem from occurring. Proper fertilization, irrigation, mulching and pruning will maintain the health of the trees and support their natural defenses against insect and disease pests.