Can I prune a crepe myrtle tree now? If yes how far back can I cut it back?
You can prune it now. Many crape myrtles in our area have a lot of dieback from our harsh winter, some completely to the roots. Any branches that are dead should be removed.
In the best case scenario crape myrtles are planted in sites that are suited to the size they want to be naturally, i.e., they don't need to be pruned.
If you need to though, they can take a hard pruning- as much as you want- we call this 'crape murder' :) . They bloom on new wood.