Tips and resources for farmers and gardeners
The common purple lilac is a tough, reliable shrub that may reach a height of 15 to 20 feet. Unfortunately, as lilacs mature, the shaded lower portions of the shrubs usually lose their leaves. As a result, large, overgrown specimens are often leggy and unattractive.
The following year (again in late winter), prune out one-half of the remaining old stems. Also, thin out some of the new growth. Retain several well-spaced, vigorous stems and remove all the others. Finally, remove all of the remaining old wood in late winter of the third year. Additional thinning of the new shoots should also be done. Since lilac wood needs to be 3 or more years of age before it blooms, this pruning method should allow you to enjoy flowers every spring.
When properly pruned, an overgrown lilac can be transformed into a vigorous attractive shrub within a few years.
University of Nebraska-Lincoln Extension
Iowa State University Extension
Montana State University Extension
Ratchet Anvil Pruner
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