Ah, the sweet scent of lilac blossoms – what better sign of summer’s arrival? But what about that overgrown thicket that seems to be producing smaller and fewer flowers every year? The solution is as easy and laid-back as the shrub itself. A simple three-stage pruning will bring back the vigor:
1. Lilacs develop next year’s flower buds shortly after this year’s blossoms are done. So the most rewarding way to improve your lilac is to simply cut large bunches of blossoms at their prime. This will allow the plant to direct maximum energy and nutrients toward stronger buds for next season. Another option is deadheading the shrub – remove spent blossoms just below their base right after bloom. If you wait until later in the summer to prune, you will be trimming the newly forming buds instead. Ordinary hand clippers are the best tool for the job, as you want to maintain the natural shape of the shrub.
2. With a sturdy pair of loppers, cut any diseased, poorly shaped and severely aging stalks off near ground level. One exception here: If you have one of the newer grafted varieties of lilac, make sure your cuts are above the graft union or you will lose the characteristics of your variety. More sunlight in the interior of the shrub will encourage bud development. Added air circulation will also keep mildew, a common lilac disease, at bay.
3. As numerous suckers poke up from the ground, save the strongest third of them and remove the weaker ones. Although it may take these new shoots three years to flower, you should start getting larger, stronger blooms from the older branches in a season or two. You can then continue this process annually or do a more serious renovation every three to five years.
Stella Otto is the nationally recognized author of The Backyard Orchardist and The Backyard Berry Book. [email protected]