Rejuvenation Pruning of Shrubs
Many shrubs can be easily renewed with rejuvenation pruning. The shrub is cut entirely to the ground in the early spring or late fall before growth starts. The shrub regrows from roots, giving a compact, youthful plant with maximum bloom. Rejuvenation can have a major effect on size. This method is preferred for many flowering shrubs because it is quick and easy with great results. Initial rejuvenation should be followed by thinning new canes to several strong ones over the next several
years. Remove weak cane growth at the base (ground level).
Rejuvenation is typically done no more than every three to five years when a shrub begins to look gangly and woody. It works very well on multi-stemmed, twiggy type shrubs such as spirea, Potentilla, dogwood, sumac and hydrangea. renewed each spring.) Also use this method to rejuvenate lilac, barberry forsythia, honeysuckle, mockorange, flowering weigela, viburnums, and others.
This method does not work with coniferous or evergreen plants such as Juniper or Cedar.
• Spring-flowering shrubs will not bloom the year of rejuvenation.
• On shrubs with a rock and weed fabric mulch, rejuvenation may not be successful due to decreased root vigor and interference of the mulch with growth from the base.
• Extremely overgrown shrubs with large woody bases may not respond
well to rejuvenation pruning.
• Shrubs with many dead branches will not respond well to rejuvenation pruning. As a rule of thumb, if more than one-third of the branches are woody, without healthy foliage, the shrub will probably not respond.
Shrubs that have been repeatedly sheared often become woody and filled with dead twigs. The best option may be to replace them. On many commercial sites, labor issues prohibit routine pruning. When shrubs become overgrown, they are simply replaced as a low-maintenance alternative. Shrubs can also be overwhelmed by weedy
invaders. If routine clearing of these invading woody species is not done, the original shrubs may be compromised or lost. Replacement may again be needed.