Answer: There are two approaches to pruning these shrubs. A newly purchased plant will probably stay stocky for about a year or so and then it will begin to become gangly; this is because most of them are treated with growth retardents to keep them dense. Once that wears off, they revert to their natural more tree-like and wild shape. Some gardeners will trim out unruly branches on an ongoing basis all year so as to avoid interrupting the flowering cycle. Other gardeners will opt to cut them back quite hard in late winter just before the spring growth flush. This can help encourage bushiness and control size and can be done in conjunction with root pruning and/or repotting. Either way seems to work.
Q&A Library Searching Tips