Tips on Pruning Hydrangeas

Hills-of-Snow Hydrangea (Hydrangea arborescens)

• The Hills-of-Snow variety is sensitive to the cold temperatures of the winter season. In addition, it produces most of its blossoms only on its newest growth. Thus, the University of Rhode Island advises gardeners to prune the shrub down to the ground every winter. If you'd rather have a larger shrub and less flowering, the university suggests cutting all of its branches down to lengths varying between 12 to 36 inches. Stagger the pruning so the plant retains its general shape.

Oakleaf Hydrangea (Hydrangea quercifolia )

• The Oakleaf variety earns its names from the way its leaves mimic the shape of the oak tree's foliage. Some of its branches may die during the winter. In the early spring, Cornell Cooperative Extension suggests pruning back the shrub to cut off any dead wood, identified as dark brown to black branches that break or bend easily. Otherwise, only trim the live growth to keep the shrub the size that you want it.

Pee Gee Hydrangea (Hydrangea paniculata)

• The Pee Gee variety is anything but a small plant, though its name may sound like it. It grows very vigorously, and the University of Rhode Island warns that failing to prune it will result in a very overgrown bush. Prune as needed throughout the year to trim back its newly sprouted shoots and keep the shrub the height and width you want. In the early spring, trim off the older, woodier branches back by no more than 1/3 of their original length.

Hortensia Hydrangea (Hydrangea macrophylla)

• The Hortensia variety is one of the most commonly raised varieties of hydrangea, reports the Cornell Cooperative Extension. For the best results, prune the plant in the late summer. Identify the smaller, weaker shoots that sprout up from around the base of this upright, vertical-growing shrub and cut them to its base. The extension suggests keeping several of the older, woodier branches, too. This helps keep the shrub strong, and the newer, flowering branches are arranged around the support of the older branches.