The three most common reasons for their confusion are the plant’s dead-looking appearance in winter, its failure to bloom in summer, and the reasoning that because it’s a shrub it needs to be pruned. But these popular woody plants can live long, floriferous lives without ever feeling the cold blade of a pair of Felcos. Hydrangeas, though, can handle pruning (which, if done at the wrong time, may be the cause for the lack of flowers), and sometimes you might want or need to cut them back a bit. For example, you may not like the look of the fading blooms or your shrub may be a bit too tall. Pruning hydrangeas can also improve a shrub’s vigor and increase the size of its flowers.
Not all of these shrubs should be pruned at the same time. Those that bloom on old growth should only be pruned after flowering. Others bloom on new growth and should be pruned before they wake up in spring or as they are going dormant in fall.