It is common to get calls in early summer by homeowners wanting to know what is wrong with their peach or nectarine tree. Infected leaves pucker, become deformed and turn yellow or reddish-brown. Unfortunately, by that time, when symptoms are most evident, it is too late to spray anything. Leaf Curl is the culprit and is one of the most encountered diseases in unsprayed orchards and home yards during cold, wet springs. Diseased leaves eventually wither and fall from the trees. Although new leaves emerge from dormant buds, their growth requirements reduce yield and may weaken the trees.
To prevent leaf curl disease, spray peaches and nectarines with a fungicide before bud swell (EPP-7319 - Home Tree Fruit Production and Pest Management). Apply when the trees are dormant and temperatures are above 40 degrees Fahrenheit, usually mid-February through March depending on weather and location in the state. Bordeaux mixtures, copper flowable fungicides, chlorothalonil and lime-sulfur sprays are commonly used for control of leaf curl.
