All peaches can get Peach Leaf Curl. Prevent by spraying the entire tree with liquid copper or with a fungicide that contains chlorothalonil in late winter/early spring before the buds swell and the bud scales crack open. The major insect pest in Wisconsin is Plum Curculio which is primarily a pest from late May to mid-June (spray insecticide if necessary).
Wisconsin is not a major peach-growing state due to our cold winters. The best success will be obtained by planting only very cold-hardy varieties. Contender Peach is being successfully grown in Wisconsin. While it is rated for Zone 5, it has been successfully grown in some areas of zone 4 when in a protected site.