Gardening expert Michael Griffiths has urged gardeners to perform a simple summer prune on climbing hydrangeas in July to encourage a second flush of flowers. In a recent video, Griffiths explained that climbing hydrangeas, which typically flower between June and August, can benefit from a quick trim after their initial bloom.
How to Prune Climbing Hydrangeas in Summer
Griffiths advises inspecting the plant for spent flowerheads—those that are droopy, wilted, or discoloured. Gardeners should then trim the stem about an inch above any new buds. This directs the plant's energy toward new growth rather than maintaining old flowers.
“Climbing hydrangeas can also be pruned after flowering,” Griffiths said. The process is straightforward: simply remove leftover flowers to make way for new buds later in the summer.
Benefits of a Summer Prune
Removing spent flowers diverts energy from dying blooms, stimulating side-shoot growth. A summer prune also helps build healthy wood for next season's buds and improves light and air circulation through the vine. Additionally, it keeps the plant looking tidy.
However, Griffiths warns against a hard prune in July. Gardeners' World notes that if a climbing hydrangea has grown too large, a harder prune in autumn or spring may be necessary, but this could sacrifice flowers for a few years.
Common Pruning Mistakes
Climbing hydrangeas produce flowers on last year's shoots. To allow time for flowering wood to develop, prune in summer right after flowering. Gardeners' World advises: “Don't cut the plant back too much.” Incorrect pruning is a common reason for poor flowering on mature plants.
