Unless you are in the mountains, Arizona is a state with hot summers and mild winters. Normally such conditions are hostile to peach trees and will result in little or no fruit production. Thankfully, there are some white hybrid peach tress that grow well and produce fruit in Arizona.
Plant white peach trees where they will be protected from the harsh afternoon sun, ideally where there is afternoon shade, and in sandy, loamy, well-draining soil.
Dig a hole for the bare-root tree that is twice as large as the root ball and 6 inches deeper. Mix equal parts compost and soil for refilling the hole.
Place the tree's root ball into the hole. Cover the hole with the compost-soil mixture. Make a well for watering that is 4 inches deep and 3 feet in radius from the tree.
Fill the white peach tree's well with water in the morning using a garden hose. Allow the water to absorb into the soil. Repeat the watering to encourage the tree's roots to grow deep in search of moisture.