I planted lilacs three years ago and they have grown tall, spreading out wide, shooting out more stems, and look very healthy but no flowers. What can I do to start them blooming?
The Gardener’s Answer
Hi, Hiroko: There are a few reasons why your shrubs are not blooming. Lilacs do not bloom as young plants and it can take them at least three years before they produce their first flowers. Depending on the age/size of the plant you purchased, this may be the case. If you planted them bare-root it could be even longer before you see any flowers. It is essential for these shrubs to be planted in full sun. They will not bloom well if they do not receive a minimum of six hours of direct light. If this is not the case for your shrubs, then you should consider moving them to a sunnier location. Over-feeding our plants can also cause them not to bloom. If you are fertilizing your shrubs, be sure to follow recommended rate applications for the product you are using. I assume you have not pruned your lilacs; pruning too late in the summer can remove flower buds for the following season. From the information you gave, I suspect your shrubs are just too young to bloom. It sounds like they are very healthy otherwise, so I would say just be patient and it will be worth the wait.