Our oak leaf hydrangea bloomed beautifully this year, and the flowers have turned pink or brown but they’re still on the plant. The shrub is huge and needs to be cut back. Is it too late to prune it now? I want to make sure it blooms again next year.
Landscape designer and plantsman Troy Marden, in his book Southern Gardener’s Handbook, says that pruning oak leaf hydrangea can be “tricky.” It blooms on old wood, and next year’s buds may already have begun to develop. If you prune it now, mid-August, you likely will be cutting off some of next year’s flowers. Best to prune the plant shortly after the flowers have turned from white to beige, he suggests.
There’s no reason you can’t remove any dead branches or stems now, though. Use sharp pruning shears, and cut dead twigs and stems off close to the branches. In fact, hydrangea experts note that dead stems should be removed every year.
Shortly after the shrub blooms next spring, consider removing about a third of the older living stems at ground level, which should revitalize the plant.