Care for an ornamental peach tree begins even before the tree is planted. It begins with gaining knowledge as to the various cultivars available, their hardiness zones, space requirements, and soil preferences. All of these things are important to the health of your peach tree. Basically, peach trees need full sun, well drained soil, and adequate air circulation for growth and fruiting. When purchasing a peach tree look for one that is approximately a year old, and 4-5 feet in height. (You can also purchase bare root trees, which are lower in cost, and easily transplanted.) Early spring is the optimum time to plant a peach tree.
Dig a hole twice the size of the root ball, and to its former planting depth (depth of the container, or root ball, or to the soil line of a bare root plant). Break up any clumps of soil, and loosen the soil on the sides of the hole so that the roots of the peach tree can easily grow into the soil.
Place the tree in the prepared hole, and spread the roots out. Fill in the hole with soil, and water thoroughly.
Water a newly planted peach tree twice a week (assuming there hasn't been any rain). Continue watering two times a week during the first growing season.
Fertilize a newly planted peach tree a month and a half after planting by applying a water soluble fertilizer (10-10-10). This should be applied around the drip line of the tree. Fertilize peach trees twice a year -- once in the spring when the buds are just beginning to appear, and again in the fall after you have picked the last of the fruit.
Thin the fruit so that the weight of the fruit does not break the branches/limbs of the tree. The rule of thumb is fruit/peaches every six inches on the branches. After spring blossoming, approximately four weeks when the fruit is beginning to form, remove or thin the fruit. You just have to pluck the forming fruit from the branch. Not only will this save the branches from breakage but it will produce larger peaches.
Prune away any dead, diseased, or broken branches immediately. Do not put diseased plant material in your compost bin, and disinfect your cutting tools by dipping the blades in alcohol or bleach. Also, prune away any suckers (shoots that grow up from the bottom of the trunk at ground level, or shoots growing up from the roots). Heavy or severe pruning should only be done when the tree is dormant, which is in early spring before any buds appear. You want to prune to create an open "V" shape.
Apply an insecticide/fungicide during the growing season to prevent/control pests and disease. Follow the manufacturer's directions.