Peach trees are very susceptible to a fungal disease called peach leaf curl. It manifests as curled leaves and lack of growth. Did you notice the leaves curling? I could be of more help if I see the tree as it becomes sickly. The practical solution here is not to plant peach trees. They really are one of the more difficult tree fruits to grow but the one variety that shows some resistance to peach leaf curl is "Frost".  To discourage fungi keep foliage dry and improve air circulation by giving plenty of room around trees. Keep growing, Marianne Binetti