Pruning hydrangeas is easy to do, and will help in providing more blooms for the following growing season. Hydrangea pruning varies slightly from species to species, depending on when and where the plant will bloom. After the blooms have finished their season, removing them will allow the plant to focus its energy on storing food for the coming winter. When the winter comes, it is important to not cut off the brown stems. It is on these stems that the plant will bloom the following year. Pruning hydrangeas in the winter can entail topping off the plants in order to shape them. There should only be an inch or so taken off smaller plants and three to five inches taken off larger plants. The cut should be done just above a joint.
The following winter, these brown stems will become a whiter color and are ready to be removed. Pruning hydrangeas at this time involves removing these white stems, so new growth will be encouraged. Pulling gently on the white stems should remove them. If not, they may not be ready yet, and will be in a few months.
Pruning hydrangeas that are large and mature can affect the blooms of the following year. Removing brown stems will result in fewer but larger blooms. Leaving the brown stems will provide more but smaller blooms.