Hydrangea: when and how to prune

Hydrangea macrophylla

Prune a hydrangea in March–April, and lightly: cut off the old flower heads just above the first pair of fat buds, because the mophead hydrangea flowers on last year’s wood.

On a mophead or lacecap hydrangea, this summer’s flowers are already waiting as fat buds at the tips of last year’s stems: shorten everything in spring and you cut off the flowers. So first check which hydrangea you have.

Updated on 11 October 2026

Key facts
Pruning months	March–April
Nesting season (15 March–15 August)	Take care in March–April
Flowering	June–September
Good for bees, butterflies and birds	Little
Native to Belgium	No, planted

Hydrangea: when to prune it?

Prune in March–April, once the hardest frosts are over and you can see the fat buds swelling. Leave the faded flower heads on over winter: they protect the buds beneath them from frost.

If a night frost threatens after pruning, cover the shrub with horticultural fleece: frozen buds at the stem tips mean a summer with few flowers.

Panicle hydrangeas and the smooth hydrangea ‘Annabelle’ flower on new wood and can be cut back firmly in March; prune a mountain hydrangea like a mophead.

What else to prune in those months? March · April

Hydrangea: how to prune it?

First check which hydrangea you have: large balls or flat heads in pink, blue or white with glossy leaves point to a mophead or lacecap. Cone-shaped flower heads belong to a panicle hydrangea, large white balls on thin stems to a smooth hydrangea.
Cut each old flower head off just above the first pair of fat, healthy buds below it. Keep those buds: that is where this summer’s flowers come from.
Cut or saw one or two of the oldest, thin or dead stems off at the base, a few more on a large shrub: that lets light into the shrub and keeps it young.
Cut frost-damaged tips back to the first healthy pair of buds; remove a stem without any live buds at the base.
Repeat-flowering (remontant) varieties also flower on new wood: pruning too hard costs them fewer flowers, but their first flush of the year still comes on old wood.
Keep prunings away from rabbits, guinea pigs and other pets that nibble: hydrangea is mildly poisonous.

How much to cut, and how often?

One light prune every spring: the old flower heads, and one or two old stems at the base. Nothing more is needed.
If the shrub has grown too big or bare at the bottom, renovate it over three years: each spring, take a third of the oldest stems out at the base. It will carry on flowering meanwhile.
Cutting a mophead hydrangea right down is a last resort: it usually regrows, but often doesn’t flower for a year.

What does it mean for wildlife?

Blackbirds and dunnocks sometimes build a nest in a well-filled hydrangea. Pruning in March–April falls in the nesting season (15 March–15 August): look between the stems first, as disturbing an active nest is against the law.
The large, coloured florets of mophead hydrangeas are sterile and have little to offer bees. Lacecaps and mountain hydrangeas have small, fertile flowers in the centre, which do attract bees and hoverflies.
The dry flower heads you leave on over winter don’t just protect the buds: spiders and small insects shelter in them.
Prunings can go on the compost heap. For more wildlife, plant a native shrub with similar flower heads next to your hydrangea, such as guelder rose: bees on the flowers, and berries for the birds in winter.

Common mistakes

Cutting a mophead hydrangea right back in spring or autumn, so it doesn’t flower that summer.
Removing the old flower heads in autumn: the buds are then exposed all winter.
Shortening every stem a little each year: you keep cutting off the flower buds and get mostly leaves.
Pruning a panicle hydrangea like a mophead, or the other way round: check which one you have first.

Caution: Don’t prune a bigleaf hydrangea any harder: it flowers on last year’s wood, and if you shorten every stem, you cut off the flowers.

Nearby: related pruning guides

Plant profile: Hydrangea · Pruning calendar and basic rules