Perennial

Yarrow

Achillea millefolium · Asteraceae · also called achillea, milfoil
By Hannah Price · Updated

Yarrow seasonal calendar
JanFebMarAprMayJunJulAugSepOctNovDec
FlowersFlowers in JuneFlowers in JulyFlowers in AugustFlowers in September
PlantPlant in MarchPlant in AprilPlant in MayPlant in September
PrunePrune in JulyPrune in October
Looks goodLooks good in JuneLooks good in JulyLooks good in AugustLooks good in September

Overview

Feathery, aromatic leaves form a mat from which stiff stems carry broad, flat heads of tiny flowers all summer. The native white wild form grows in lawns and meadows across Britain, while garden selections cover a wide palette: 'Paprika' is brick red, 'Terracotta' fades from orange to buff, and 'Lilac Beauty' is soft mauve. The flat heads make landing pads for hoverflies, small bees and soldier beetles, and they dry well for vases. Colours on many hybrids fade softly as the flowers age, so a single plant often shows several shades at once.

Where to grow yarrow

Choose an open, sunny spot with free-draining soil. Yarrow is ideal for gravel planting, prairie-style borders and coastal gardens. On heavy clay, add grit or grow it on a slope, because winter wet rots the roots.

Planting

Plant in spring or early autumn, 40–45 cm apart. Skip the compost and fertiliser; lean conditions keep stems upright and colours strong.

Care through the year

Spring

Divide or plant new clumps. Insert twiggy supports in exposed gardens.

Summer

Deadhead the first flush to encourage more flowers; water only new plants.

Autumn

Leave some seed heads standing for frost-rimed winter shapes.

Winter

Cut the old stems down by late winter if they collapse.

Pruning

After the first flush fades in July, cut stems back to a strong pair of side shoots. Clear spent growth to the basal rosette in autumn or late winter.

Propagation

Divide clumps every two to three years in spring, discarding the woody centre. Basal cuttings taken in spring also root easily.

Common problems

Powdery mildew can appear in dry, crowded borders; improve air flow. Plants collapsing in the middle usually need dividing. The species can spread by runners, so give it room or choose clump-forming cultivars.

Something else wrong? Diagnose it by symptom.

Month-by-month reminders

Jobs for this plant come round in March, April, May, July, September and October. Each month page lists everything else worth doing in the garden at the same time.

Related plants

Sources

Botanical names follow Kew's Plants of the World Online; growing attributes were checked against the references below. Text is our own. See our editorial policy.