Lilac Bush Not Blooming? Here’s What to Do

Why Is My Lilac Bush Not Blooming?

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“I was given a small lilac bush years ago from a friend’s garden. Every spring I’m so disappointed to see no flowers. How can I get it to bloom?” asks Birds & Blooms reader Georgette Jahn of Dingmans Ferry, Pennsylvania.

Horticultural expert Melinda Myers: Shade and improper pruning can prevent lilacs from flowering. Make sure your plant receives at least six hours of sunlight. If not, consider moving it to a sunnier location. Avoid high nitrogen fertilizer because it can prevent flowering. Only prune lilacs right after their normal bloom period in early summer if you want flowers the following spring. Pruning at other times eliminates the flower buds and your spring bloom.

We asked the experts: here’s how and when to prune lilacs.

Why We Love Lilacs: So long-lived that it often survives even after a house is long gone, a lilac bush needs no coddling beyond regular watering its first year.

Does a hydrangea need full sun or shade to grow best?

Do Lilacs Like Acidic Soil?

Via Proven Winners

“My lilac bushes have never bloomed. They get some direct sun, but some shade. The soil is acidic because of pine and oak trees. Is this the problem?” asks reader Joanne Eastman of Lovell, Maine.

Melinda Myers: Evergreen needles and oak leaves have little to no impact on soil acidity. Plus, acidic soil would cause leaf discoloration and stunted growth, not merely a lack of flowers.

The shade from these trees may be the culprit. Lilacs flower best with at least six hours of direct sunlight. Too much high-nitrogen fertilizer and improper pruning can also result in a lack of flowers. Go easy on the fertilizing, and prune only if needed right after the lilacs should have bloomed. These plants develop their flower buds in the summer, and the buds then open the following spring.

Backyard Tip: Do you really love lilacs, but wish they bloomed longer? Check out the new reblooming lilac options out there, like Bloomerang Purple from Proven Winners.

New Age White Lilac is a fresh update on a classic shrub.