Lilac not blooming

Asked May 14, 2020, 4:49 PM EDT

I have 4 lilac bushes within 50 feet of each other. They all are the same age, I heavily pruned them several years ago and they're about 5-6 feet in height. One blooms profusely but the others not at all.

The attached photo, looking South, shows all three - the farthest in the photo is the "bloomer".

Suggestions?

Ingham County Michigan

3 Responses

Lilacs do best in full sun (generally, 6+ hours of sun). It may be only a few hours that make the difference. Is the one that is blooming getting more sun than the others? I am not sure what tree coverage/shade is like in your landscape.

The bush that blooms gets the least amount of sun - they all get at least 6+ (presuming the sun is shining)

After a hard prune it can take lilacs a few years to recover and set flower buds again. The one blooming lilac may just be recovering faster than the others due to less stress from the hard prune or other physiological reasons.

This article from the University of Maine can provide more insight into other reasons the lilacs may not be blooming: https://extension.umaine.edu/piscataquis/programs/home-gardening/basicgarden/lilacs/