Japanese burnet

Japanese burnet: how do you recognise it?

Habit

Loose clump about 60 cm tall and wide, with arching flower stems.

Foliage

Pinnate, with rounded to oval leaflets in grey-green.

Flower

Fluffy pink spikes that droop like foxtails, from July to September.

Roots

Rhizome that slowly widens the clump. Divides well in spring.

Flowering: July–September · Plants: March–May and September–October · Pruning: March

Why grow it?

• Flowers from July to September with soft pink, fluffy spikes that droop gracefully.
• The grey-green, finely divided foliage is already attractive before flowering.
• Compact (about 60 cm tall and wide) and ideal among ornamental grasses.
• Bees visit the flowers.
• Spreads slowly without running wild and is hardy to −25 °C.

Japanese burnet: where does it grow best?

• Full sun to partial shade; in full sun it needs more water.
• Moist to wet, humus-rich soil: loam, clay or peat, acid to neutral.
• Water in dry summers; it copes poorly with long drought.
• Allow 50–60 cm per plant; it can stand fairly loosely among grasses.

Light

Sun and partial shade

Soil type

Loam, clay or peat

Acidity

Acid or neutral

Moisture

Normal or wet

Size

0.6 m tall, 0.6 m wide

Hardiness

Hardy (to -25 °C)

Goes well with

• Ornamental grasses: Purple moor grass or feather grass make the pink spikes look airy.
• Hemp agrimony: A taller, late-flowering plant that tolerates the same damp soil.
• Michaelmas daisy: Purple flowers that go well with the pink spikes.
• Coneflower: Yellow flowers that contrast with the soft pink spikes.

Japanese burnet: when and how to plant it?

Plant in March–May and September–October.

1. Plant in March–May or in September–October, when the soil is not frozen.
2. Dig a hole twice as wide as the root ball and mix in compost or leaf mould.
3. Set the plant at the same depth as in its pot and firm the soil.
4. Leave 50–60 cm between plants.
5. Water thoroughly straight away and keep the soil moist in the first year.
6. Spread a layer of compost mulch around the plant.

Care

Water

Water generously at the base in dry summers. Mulch keeps the soil moist.

Feeding

A layer of compost in spring is enough. Too much nitrogen gives soft foliage.

Mulching

A layer of compost or leaf mould in April keeps the soil cool and moist.

Spent flower spikes

Leave them for structure in autumn, or cut them off if you want to prevent self-seeding.

Support

Support is rarely needed; the stems arch over gracefully by themselves.

Tip: Put it among ornamental grasses: the drooping spikes look their best there. Water in dry summers and divide the clump every few years.

Japanese burnet: when to prune it?

Pruning months: March.

When: In March, before the new shoots.

How:

• Cut dead stems and old foliage back to just above the ground.
• If you like, cut spent flower spikes down to the foliage in summer.
• Use sharp secateurs and clear away the clippings.

Pruning: when and how · Pruning calendar and basic rules

Propagation

Division

In March–April or September–October, cut the clump into pieces with a spade, each with roots and shoots, and replant at once.

Seed

Seed germinates best after a cold spell: sow in autumn in a seed tray and leave it outdoors until spring.

Japanese burnet: how does it get through the winter?

Hardy to −25 °C.

• Hardy to about −25 °C: no protection is needed in Belgian winters.
• The foliage dies back in late autumn; cut it away in March.
• Give plants set out in autumn a layer of leaves or compost as extra protection.

Diseases and pests

• Drought stress: Leaf edges turn brown and the plant wilts. Water generously and mulch the soil.
• Powdery mildew: White powder on the leaves in late summer, especially in dry weather. Water at the base and cut off affected leaves.
• Slugs: They eat young shoots in spring. Collect them in the evening and protect the new shoots.
• Worn-out clump: Old plants become bare in the middle or flower less. Divide them in spring and replant the young pieces.

Through the year

• March: Cut back dead stems and old foliage. Add compost. Plant or divide.
• April: Plant or divide. Apply mulch.
• May: Plant. Watch for slugs.
• June: Water in dry weather.
• July: Flowering begins. Water in dry weather.
• August: Full flower. Keep the soil moist.
• September: Last flowers. Plant or divide.
• October: Plant or divide.
• November: Foliage dies back. Dormant.

Good for wildlife

Bees

Nectar and pollen for honeybees and wild bees.

Did you know?

• The genus name Sanguisorba combines the Latin sanguis (blood) and sorbere (to soak up) and refers to the use of burnets in old herbal medicine.
• In Flanders the great burnet (Sanguisorba officinalis) grows wild in damp hay meadows; related species come from Asia and North America.