Answer: Summertime is a difficult time for newly planted trees and shrubs. The weather is harsh and while they are trying to re-establish their roots, they must also contend with hot sunshine and warm temperatures. If you followed the planting recommendations and are giving them enough water, they should recover. Before giving up on your purple leaf cherries, try checking to see if the branches are still alive. It's possible that they just dropped their leaves due to stress and will recover. Scrape the bark from some of the branches. If you see green tissue, the branch is still alive; brown tissue means it is dead. If there's enough green on the branches, you should see new leaves later in the season. If the branches are dead, you may want to replace the plants. I'd suggest waiting until fall when the weather is cooler, or spring, to replant the cistenas.
Best wishes with your garden!
Q&A Library Searching Tips