Light Heading Back:
Light heading back is the procedure where branch tips are removed. This will control the shape of a mature shrub and increase bloom. The cut should be made approximately 1/4″ above a healthy bud.
Severe Heading Back:
Severe heading back is the removal of approximately half of nearly every branch. This stimulates the production of fewer, but larger flowers on a few strong stems.
Thinning is the removal of a branch to the ground or back to the main branch. This process will make the shrub less dense and encourage the strong growth of the existing branches.
For all pruning techniques, the cut should be made at an angle a quarter of an inch above a bud. If cut any closer, the bud probably will not survive; any farther, the branch will die. The cut should be made toward a bud on the outside of a branch. This will generate foliage growth to the outside of the branch, giving shape to the plant. By angling the cut, water will easily run off, therefore, discouraging disease.