Lilac should only be pruned within two weeks of the flowers fading. Many people prune their lilac in the fall or early spring, and they cut the flower buds off. Shrubs also have way too many stems coming out of the base. Each plant every season has a finite amount of energy that it can produce with the roots and leaves that it has. If we have too many stems, then each stem is not getting very much energy out of the bank account and that is why we only get very small flowers on our lilac. So we n

How To Prune Overgrown Lilacs