Q: I purchased a peegee shrub and need to know how and when to prune it. It had many blooms and now has a bad case of flopping downward. What to do?
A: With a complicated name like Hydrangea paniculata ‘Grandiflora’, it’s understandable than gardeners call this plant “peegee” hydrangea.
Unlike the common mophead hydrangea, peegee hydrangea produces cone-shaped blooms on new wood. In other words, you can prune it severely in winter and it will bloom nicely the following summer. Decide how tall you want yours to be each summer and cut it to half that height in January. It will have stocky central stems from which limber blooming branches will emerge.
You can also leave it unpruned. Garden favorite Hydrangea paniculata ‘Tardiva’ produces its spectacular twelve-inch long blooms in mid-summer.