When to plant Hydrangeas
Calendar windows
Dates shift with your latitude — they are calculated from your local last-spring-frost date, not from a fixed calendar.
At a glance
Takes frost; can go out weeks before the last one.
Practical notes
Soil pH sets the colour of mophead types: acid soil gives blue, alkaline gives pink, and white varieties ignore both. Know which species you have before pruning — cutting a mophead in spring removes every flower bud.
Knowing when to pick
For drying, leave the heads on the bush until they turn papery in late summer — cut too early and they wilt instead of drying.
Storing the crop
Dried heads keep their shape for years indoors, out of direct sun. Leave last year’s heads on the plant over winter — they shelter the buds beneath.
Crop rotation
No strict rotation group — still avoid replanting into the same soil year after year.
Grows well with
Keep apart from
Watch for
Full guide: hydrangeas diseases and pests (3) → with spread routes, compost verdicts and the prevention this list justifies.