When to prune hydrangeas?

CandideZA
Published on July 31st 2019
21
A close up of a flower
Not all hydrangeas are pruned at the same time so it is important to establish what variety you have before you head out into the garden with your secateurs.
Here are some tips on how and when to prune Hydrangeas:

Hydrangeas that bloom on old wood

These hydrangeas produce new spring blooms on last year’s buds. They bloom in early summer and flowers die by mid-summer.
Varieties include Hydrangea macrophylla (Bigleaf Hydrangea, Mophead, Hortensia, Lacecap), H. serrata (Mountain Hydrangea, Lacecap) and H. quercifolia (Oakleaf hydrangea).
When to prune:
  • Just after its blooming peak and just before blooms begin to fade mid-summer.
  • Trim before it starts producing buds or you will risk cutting off next year’s growth.
How to prune:
  • Remove old blooms - deadhead spent blooms by clipping just under the heads at the tips of the stems.
  • Remove dying canes - trim at their base.
  • If your hydrangea has grown too large and takes up too much space, prune it just after blooming season to reduce the size.
A close up of a flower

Hydrangeas that bloom on new wood

These hydrangeas produce new growth each spring, then bloom from that growth later in the summer. They tend to bloom later than hydrangeas that bloom on old wood as they need the extra time to create buds.
Varieties include Hydrangea paniculata (Panicle hydrangea, PG hydrangea) and H. arborescens (Smooth hydrangea, Annabelle, Snowball).
When to prune:
  • Prune in late winter or early spring before bud generation begins and do not prune right before they go into bloom.
How to prune:
  • Prune dead canes and crossed branches - this will allow for better airflow and encourage healthy growth.
  • Leave some old branches to support the heavy flowers and to the plant grow well.
Pruning your hydrangeas will improve the shrub’s vigour and increase the size of its blooms. Maintain health and shape of your hydrangeas by removing damaged stems when noted and cutting stems that detract from the overall form. Hydrangeas are pretty tough and if pruned at the “wrong” time, don’t stress, you’ll only miss one season of bloom.
A close up of a green plant
Free download for your phone or tablet
Download on the App StoreGet it on Google Play

Lots to see

Follow and read AlanGardenMaster’s articles as he develops his new one-acre plot. PimlicoDan shows city gardening in a whole new light, or follow DaisyDays on her adventures in the allotment and as a professional gardener. Just a few of the many personalities you’ll meet in our app. Free download for your phone or tablet.
Download on the App StoreGet it on Google Play