Japanese Lilac

Asked May 23, 2018, 12:37 PM EDT

Our Japanese lilac has not developed flower buds yet this year, so I'm concerned that something happened over the winter. The leaves are healthy and the tree itself looks great. This is its fourth year; the first year there were some flowers when it came from the nursery, the second year there were none. Last year there were many flowers--we thought we were on our way to annual blooming. Thank you for any thoughts you might have. Karen

Hennepin County Minnesota

3 Responses

Have you pruned it? Pruning should only be done just after flowering. If it doesn't flower prune just after other lilacs bloom. Has it been fertilized? that can cause excessive leaf production. Sometimes they get too much lawn fertilizer even if not fertilized directly. They also need regular watering.

Hi Evelyn,

Thank you for responding to my question! The only one of the things you mentioned might fit--the regular watering. We haven't pruned it at all, we don't fertilize it or the back yard because we have dogs and I don't like chemicals around them.

So I should prune it when the lilacs have finished. Would I prune just the ends or do more of a shaping prune? I always think I should let things grow when they're fairly new, but does a pruning help with the flowering?

I'll make it a point to water regularly---I do when we're in the dryness of August/September, but haven't made sure it's been done regularly.

Thank you very much for your help on this!


Pruning at the wrong time is a common cause of poor to no flowers. They are also a full sun tree and the amount of sun influences flowering. I hope this information is useful. http://homeguides.sfgate.com/prune-treetype-lilacs-24549.html