My lilac bushes have zero buds. So how will I have flowers the week before Memorial Day? That's typically when my half dozen bushes are popping with clusters of deep purple and pale lavender blossoms. My neighbor’s bushes are already sprouting lilacs. This week, I drove on a frontage road along Hwy. 100 in St. Louis Park and longingly gazed at the remnants of  “Lilac Way” in all its purple glory.

Then I remembered that my husband had pruned every single one of the 12-foot-tall towering plants. But when?  “Last fall,” he said. That explained why I wouldn’t have purple bunches to decorate the tables. When it comes to pruning lilacs - it’s all in the timing.

Lilacs and other spring-flowering shrubs, such as azalea and forsythia, bloom on old wood, which means that the flower buds form on the stems during the summer, but don’t open until the following spring. The fall pruning likely removed the emerging buds, canceling my spring flower show.

So if you really need to hack down those hulking bushes - do it right after the flowers have faded. The University of Minnesota Extension’s “Pruning Trees and Shrubs”  details why you should prune, when you should prune, how to prune, and the best tools to use. Go to www.extension.umn.edu/garden/yard-garden/trees-shrubs/pruning-trees-shrubs.

Photos: Schumacher's Nursery and gardenweb.