For whomever is interested, In zones 4 and colder it can behave like a perennial in and die back in the winter. Simply cut cut back any dead branches, as you would with a perennial. It quickly grows to form a nice plant the following spring. In zones 5 and warmer it grows like a typical shrubs, although hard pruning every few years results in a fuller, bushier plant.
Forms its flower buds in later summer and then flowers in early June. The best time to prune is it after it blooms, from mid-June to mid-August. Cease pruning in mid-august to allow time for the flower buds to form prior to winter.
As a young plant it is best to prune or pinch your plant in order to build a full bodied, well branched plant. If the plant is leggy when you purchased it, shear the plant back hard by 1/3 to 1/2 its original size. Once it puts on an inch or two of growth, pinch the branch tips to remove just the growing tip. This tip controls branching. Once the tips are removed the buds below it will turn into stems. Once these new branches grow an inch or two, pinch the tip out again. You can repeat this throughout the first growing season as you are tending your garden. Although you will sacrifice one year of bloom, this technique results in a well branched, full bodied plant that will have more flowers in subsequent years. The second season in the ground, repeat the pinching practice (or lightly shear) up until mid-August. Cease pruning and pinching to allow the flower buds to set.
During the third and subsequence seasons, prune or pinch after flowering and up to bud set in mid-August. Do not be afraid to prune or shear your plant harder if you wish to maintain a shorter size.
Now I know, and so do you!! :o)
