The Rockdale Gardener

Gardening Posts From Rockdale Cooperative Extension

How to Prune Hydrangeas

Here is a great article on caring for hydrangeas from the UGA URBAN AG CENTER.

The information on pruning is particularly useful this time of year.

Hydrangea: A Southern Tradition

from the article:

How to Prune Hydrangeas:

How and when to prune hydrangeas is an issue for many gardeners, even those with experience.

Pruning is done to:

  • reduce plant size or reshape plant
  • remove old, non-productive branches
  • remove frost damaged leaves
  • deadhead blossoms

Below are pruning guidelines for each of the five popular types of hydrangea listed in the table above.

Bigleaf Hydrangea (Hydrangea macrophylla) Flowers bloom on last year’s wood. In early spring remove older, woodier branches at ground level to allow more light and air circulation. (Note: Determine whether or not a branch is dead by scratching the bark with a fingernail or small knife. If there is green directly beneath the surface, the branch is alive.) After the last frost date, around mid April, clip or pull off any frost damaged leaves.

Do major pruning and reshaping after the blooms begin to fade in July, but no later than August 1st. On a mature bush (5-6 years old) remove 1/3 of the oldest woody stems each year by cutting to the ground. Encourage further new foliage growth by deadheading (removing faded flowers).

Oakleaf Hydrangea (Hydrangea quercifolia)

This is a large shrub that should be left to grow in its natural form. Flowers bloom on previous season’s wood. Prune after flowering only to remove dead wood, old flower heads and 1/3 of the oldest wood (to increase light and air circulation). If necessary, severe pruning (back to only two buds at the base of each stem) may be done in early spring (late February to early March) to renew overgrown plants.

Peegee Hydrangeas (Hydrangea paniculata ‘Grandiflora’)

Flowers develop on new wood. Plants may be handled in two ways: 1). Cut back severely to leave only two buds at the base of each stem in early March. or 2). Allow plant to develop without pruning. Blooms will still appear on new growth. Severe early pruning produces a smaller plant with larger blooms; not pruning produces a larger plant with many smaller blooms.*

Smooth Hydrangea (Hydrangea arborescens ‘Annabelle’)

Flowers bloom on current year’s wood. Prune entire plant back to 6-12” from ground in early March.*

Climbing Hydrangeas (Hydrangea anomola petiolaris)

Little or no pruning is required. In the summer, if needed, remove unwanted shoots that have grown out of bounds. (Note: Trees are not harmed by climbing hydrangea.)

*Note: Peegee and Annabelle hydrangeas, because they bloom on this year’s wood, do not have their buds damaged by the late spring frosts that so often harm Bigleaf hydrangeas. This makes them especially well adapted to growing in the Atlanta area.