Renovating Overgrown Shrubs
Quickly tame overgrown shrubs with renovation pruning in late winter or early spring.
This drastic approach to managing shrubs is not for the timid pruner or for all plants. Many shrubs like potentilla, spirea, privet, butterfly bush, beauty bush and abelia can be pruned back to 6 to 12 inches above the ground.
Wait for new shoots to emerge. As these stems develop pinch out the tips of the new growth to control the size. Then thin out a few of the stems to ground level to make room for those that remain.
Use a ratcheting lopper or reciprocating saw to extend your reach and increase your cutting power when pruning back large or hard to reach stems. Hand pruners work well for cutting smaller stems and stem tips.
A bit more information: A less stressful way to manage overgrown shrubs is with rejuvenation pruning. One fourth to one third of the older stems are cut back to ground level each year. The height of the remaining stems can be reduced by about one fourth as well. In three or four years you have reduced the size and improved the beauty of the shrub. For more on pruning, planting and care of trees and shrubs see my Great Courses DVD, How to Grow Anything: Make Your Trees and Shrubs Thrive.