Plants do not necessarily put on growth at a normal or expected rate immediately after planting. They spend their first couple of seasons developing and extending their root system - becoming established, as it were - before putting on typical amounts of top growth. And like most trees and shrubs, junipers will push their growth in spring, so a July planting (in AZ?? really??) is already past that time frame.

Root establishment of cold climate adapted plants occurs first fall after planting resulting in normal top growth the following spring and summer. Unless plants are in poor condition.

Full establishment of any woody plant takes longer than just a single fall period of root extension. And no, it doesn't always result in "normal" top growth the following spring. With the installation of dozens of new landscapes under my belt every season, I can testify to that!!