Not knowing the best time to prune your lilacs to ensure it stays healthy is a huge mistake. You want to prune your shrubs in late spring. This timing is critical because your plants will set next year’s flower clusters right after this year’s blooms fade. If you don’t prune until the fall or summer, there’s a huge chance you could snip these buds and have fewer come springtime. Along with reducing how many flowers each shrub has come spring, it can stunt your plant’s growth. If you don’t prune them regularly and correctly, they can get overgrown and woody and set the stage for diseases. Also, older, unpruned shrubs usually produce fewer flowers and are less vibrant.

To maximize your shrubs’ blooms, prune just after the flowers bloom. Remove any diseased or dead branches to help ward off fungal disease or pest infestations. Thin out the center of the bush to promote good airflow and light and cut away any suckers or new growth at the lilacs’ base to ensure it puts more energy toward the main branches. Rejuvenation pruning is also possible for older, neglected plants, cutting back the whole thing to a foot above the ground when it’s dormant.