How to prune an overgrown lilac bush?

Asked April 25, 2017, 5:49 PM EDT

I received a lilac seedling from the National Arboretum at an event and it has grown steadily in our yard for the past 9 nine years. As you will see from the photos, it is quite overgrown. It just finished blooming and I would like to prune it, but unsure how much and if I should remove the shoots along the ground in addition to the branches. Please advise when and how to prune.

District of Columbia pruning lilac shrub

1 Response

You may want to renovate in winter when dormant. Cut back main stems to within 12-24 inches of the ground. Response is good and regrowth should be thinned but flowering will be delayed by up to three years. Suckers can be removed at any time. It is preferable to stagger this hard pruning over two to three years. Be conservative.

We are not sure but it looks like the shrub may be in the shade. They flower best in full sun.
mh