Sweet coneflower

Sweet coneflower: how do you recognise it?

Habit

Upright, sturdy perennial, 1–1.5 m tall and about 60 cm wide; forms a compact clump.

Foliage

Felted, rough, grey-green; the lower leaves are three-lobed, the upper ones undivided. Faintly aniseed-scented.

Flower

Yellow flowers of about 6–8 cm with a dark brown cone, from August to October.

Forms

‘Henry Eilers’ has petals rolled into tubes, which gives the flower a star-like look.

Roots

A solid clump with a fibrous root system that widens over the years.

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

Why grow it?

• Flowers from August into October, just when the border is quietening down.
• Sturdy stems: usually no support needed, even when the plant reaches 1.5 m.
• The hairy foliage smells faintly of aniseed when bruised.
• Bees and butterflies visit the flowers, and the seedheads stay decorative in winter.
• A good cut flower for the vase.
• Lovely in naturalistic borders, with ornamental grasses and other prairie plants.

Sweet coneflower: where does it grow best?

• Full sun: the stems stay sturdy and it flowers longest there.
• Loam or clay that does not dry out, acid to chalky.
• Normally moist; once established it also tolerates short dry spells.
• An open, sunny spot in the border; in shelter the flowers stay at their best.
• Allow 50–60 cm of space per plant.

Light

Sun

Soil type

Loam or clay

Acidity

Not fussy

Moisture

Normal

Size

1.5 m tall, 0.6 m wide

Hardiness

Hardy (to -30 °C)

Goes well with

• Ornamental grasses: Plumes of a miscanthus or panicum, for example, sway nicely between the yellow flowers.
• Michaelmas daisy: Purple and blue flowers in the same late season, a lovely contrast with the yellow.
• Ice plant: Pink flower heads in late summer and thick leaves at the base.
• Verbena bonariensis: Tall, airy purple flowers that grow up through the border.

Sweet coneflower: 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 neither frozen nor waterlogged.
2. Dig a hole twice as wide as the root ball and mix in a few spadefuls of compost.
3. Set the plant at the same depth as in its pot and firm the soil well.
4. Space plants 50–60 cm apart, ideally in groups of three or five.
5. Water in at once and spread a layer of leaf mould mulch around the base.

Care

Water

In the first year, water weekly in dry weather. Later, water at the base during long dry spells.

Feeding

A spadeful of compost in spring. Plenty of fertiliser gives floppy stems that fall over anyway.

Mulching

A layer of leaf mould in spring keeps the soil moist and suppresses weeds.

Dividing

Every 3–4 years in spring, divide the clump so the plant keeps flowering strongly.

Spent flowers

Leave the seedheads in autumn for winter interest, or cut them off to limit seedlings.

Tip: Plant it in full sun in a naturalistic border, ideally with ornamental grasses. It usually stands without support and flowers until October.

Sweet coneflower: when to prune it?

Pruning months: March.

When: In February–March, before the new shoots start.

How:

• Cut last year’s dead stems down to just above the ground.
• Cut flowers for the vase just after they open; this encourages more flowers.
• For a lower plant, cut the shoots back by about half at the end of May; it will flower a little later.

Pruning: when and how · Pruning calendar and basic rules

Propagation

Division

In March–April or September, lift the clump and divide it with a spade into pieces with roots and shoots. Replant at once and water.

Seed

Sow in a tray in spring, barely covering the seed. It also self-seeds, and seedlings often flower only after a year or two.

Sweet coneflower: how does it get through the winter?

Hardy to −30 °C.

• Fully hardy, down to about −30 °C: no protection is needed in Belgian winters.
• Leave the seedheads standing in winter: they give structure, look lovely with frost and shelter insects.
• Make sure water drains away: in clay that stays waterlogged in winter, roots are more likely to rot.

Diseases and pests

• Slugs: Young shoots are nibbled in spring. Pick slugs off in the evening or lay a barrier of coarse sand.
• Powdery mildew: White powder on the leaves in dry, stuffy summers. Give it space, water at the base and cut off affected leaves.
• Leaf spot: Brown spots on older leaves in wet summers. Remove affected leaves and do not water over the foliage.
• Aphids: On young shoots and flower buds. Ladybirds often deal with them; otherwise rinse them off with water.

Through the year

• February: Cut dead stems down to just above the ground.
• March: Plant or divide. Apply compost.
• April: Plant. Watch for slugs.
• May: Plant. Cut shoots back if wished. Mulch.
• June: Water in dry weather.
• July: Water in dry weather. Buds form.
• August: Flowering starts. Cut flowers for the vase.
• September: Full flower. Plant or divide.
• October: Last flowers. Plant.
• November: Rest. Seedheads can stay standing.

Good for wildlife

Bees

Nectar and pollen for honeybees and wild bees.

Butterflies

Nectar for butterflies.

Did you know?

• The species name subtomentosa means ‘somewhat felted’ and refers to the fine hairs on stems and leaves.
• ‘Henry Eilers’ has petals rolled into tubes, so the flower looks like a star.
• This coneflower flowers into October, often until the first frosts.