I have 2 Japanese silk lilac trees (7 years old, each around 6' tall) that have never bloomed. They are in full sun and healthy looking. Any ideas why they aren't blooming?

Thank-you, Jane Duncan

HI Jane , Frustrating isnt it? since they put their flower buds on the year before they bloom be sure not to prune them in late fall or in spring. sometimes under severe winters the flower buds might get killed but usually that is not a problem for lilacs. we did have a late spring cold spell two years ago that killed many flower buds. I would be patient. dont prune. some trees need more age before they bloom well. maybe it is literally a late bloomer. If it is growing well i doubt ther i s much you can do but wait. be sure to mulch and water during drought. Sandy