When should hydrangeas be pruned for winter?
Written by
Liu Xiaohui
Reviewed by
Prof. Samuel Fitzgerald, Ph.D.The vital key to pruning hydrangeas is to prune at the correct time for bloom type to preserve next year's buds. Bigleaf types, for example, set buds in late summer, so pruning in fall would be very bad. Panicle types, for instance, can withstand winter pruning with a lot of standing up. I always check the growth habits of each plant before every cut.
Old Wood Bloomers
- Prune after flowering: Late summer before bud set
- Remove only: Dead wood and spent blooms
- Never prune: In fall or winter months
New Wood Bloomers
- Optimal timing: Late winter before spring growth
- Cut back: Up to one-third of plant height
- Shape: Maintain natural form while thinning
Dead Wood Removal
- Identify: Scrape bark to check for green cambium
- Cut: 1 inch above healthy buds or base
- Sanitize tools: Between plants prevent disease
Do not do fall pruning to old wood bloomers. Cutting stems after August prevents next season's buds from developing. I learned the hard way when I cut back my Nikko Blue hydrangeas, and they did not bloom the following summer. Only cut out woody stems that are definitely dead during the wintery months.
Prune new wood types in late winter when the plants are dormant. Make cuts just above healthy buds, angling away from the center. I cut Annabelle hydrangeas back a third to foster strong new growth. Prune before buds swell in the spring.
To effectively determine dead wood, use the scratch test. With your thumbnail, lightly scrape the bark to look for an underlying green tissue. If dead stems are present, cut them back to healthy wood or the ground. I sterilize my pruning cuts with alcohol to prevent disease from spreading from plant to plant.
Recognize bloom ramifications of cutting or pruning inappropriately. In the case of old wood flowering types, you won't have flowers; in the case of new wood flowering types, you will! My clients achieve the best results when they practice the correct technique for their specific plant type. You're thoughtful timing results in the greatest flowering in the summer!
Read the full article: Essential Hydrangea Winter Care Guide
