Which stems are carrying your flowers?
Choose a known flowering group before deciding when to cut. If the identity is uncertain, use the unknown option rather than guessing from a flower photograph.
Identify the species and cultivar before a size-reducing cut. Photograph leaves and flowers, keep the label, and check stems again as growth resumes. Flower shape alone does not establish the pruning group.
How this works, and what it leaves out
This groups plants by flowering habit, not by flower colour or a diagnosis from a photograph. Check the actual cultivar, local climate and living buds. Damage, frost, renovation and plants trained as trees may need a more specific approach.
How to use this tool
- Find the species and, where possible, cultivar on a label or reliable identification record. Flower colour alone cannot establish the group.
- Choose ordinary old-wood, new-wood, confirmed reblooming or climbing hydrangea. If the identity is uncertain, keep the unknown option.
- Use the result as a pruning approach, then check living buds, damage, climate and any named-cultivar instructions before making cuts.
Two hydrangeas can need different pruning windows
A panicle hydrangea belongs to a different flowering group from an ordinary bigleaf hydrangea. Cutting living bigleaf stems down in winter or spring can remove buds carried on older growth; a panicle hydrangea flowers on current-season wood. The tool separates those routes instead of assigning every hydrangea the same annual cut.
What the result means
“Unknown” is a useful result. Preserving living stems while you establish identity is different from guessing that every plant will flower on new growth. A verified reblooming cultivar can use both old and new wood, but that does not make every cut harmless. Climbing plants have their own framework and selective-control considerations.
Questions before you start
Can this identify a hydrangea from its flowers?
No. There is no photo identification or automatic species diagnosis here. The result depends on the group you select, so check the plant identity first.
Will pruning advice explain every year without flowers?
No. Frost, bud damage, growing conditions and plant maturity can matter as well as pruning. Use the linked guide to investigate the wider situation rather than treating a cut as the only explanation.
Put it in context
Use these guides alongside the tool for the choices a calculation or decision form cannot make for you.