Spotted Joe Pye weed

Spotted Joe Pye weed: how do you recognise it?

Habit

A broad clump of sturdy, upright stems, 1.5–1.8 m tall and about 1 m wide.

Stems

Green with purple spots or wholly purple, strong and unbranched up to the flower head.

Leaves

Lance-shaped, 6–20 cm, toothed, in whorls of three to five around the stem.

Flowers

Broad, flat to slightly domed heads of small purplish-pink flowers, from July to September.

Scent

Sweet, especially on warm, still days.

Roots

A sturdy, fibrous rootstock; the clump slowly widens.

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

Why grow it?

• One of the best late-summer butterfly plants: peacocks, red admirals and small tortoiseshells are frequent visitors.
• It gives height and structure at the back of the border or by a pond.
• A long flowering season from July to September, with a sweet scent on warm days.
• The stems and seed heads stand well into winter and give insects shelter.
• It enjoys moist to wet soil, where many other border plants struggle.

Spotted Joe Pye weed: where does it grow best?

• Full sun or light partial shade; in sun it flowers most freely and the stems stay sturdier.
• Loam, clay or peat, acid, neutral or chalky; fertile, humus-rich soil.
• Normal to wet soil that never dries out: ideal by a pond or in a damp border.
• Preferably sheltered from strong wind, although the stems are usually strong enough.
• Allow 80–100 cm per plant, at the back of the border or as a specimen.

Light

Sun and partial shade

Soil type

Loam, clay or peat

Acidity

Not fussy

Moisture

Normal or wet

Size

1.8 m tall, 1 m wide

Hardiness

Hardy (to -35 °C)

Goes well with

• Miscanthus: Large grass plumes that colour late summer together with the Joe Pye weed.
• Purple coneflower: Pink flowers for butterflies at the same time of year.
• Purple loosestrife: Purple spikes in the same moist soil.
• Culver’s root: Slender white or lilac spikes as a vertical accent.

Spotted Joe Pye weed: when and how to plant it?

Plant in March–April and September–October.

1. Plant in March–April or September–October.
2. Dig a generous hole and mix in a few spadefuls of compost.
3. Set the plant at the same depth as it was in its pot and firm the soil well.
4. Keep 80–100 cm between it and other plants.
5. Water in thoroughly straight away and keep the soil moist during the first year.
6. Mulch with compost or leaf mould to keep the soil cool and moist.

Care

Watering

Water generously in dry weather: otherwise the leaves soon droop and the lower ones turn brown.

Feeding

Compost or an organic fertiliser in March–April.

Mulching

A thick layer of compost in spring keeps the soil moist.

Support

Usually not needed; in rich soil or a windy spot, a sturdy stake can help.

Spent flowers

Leave them: the fluffy seed heads look good in winter.

Tip: Mark its position in winter: it emerges late in spring and is easily forgotten when you weed or plant.

Spotted Joe Pye weed: when to prune it?

Pruning months: March and May.

When: Leave the stems standing all winter and cut them back in March. For a shorter plant, cut the stems back by a third in late May.

How:

• In March, cut all the old stems down to about 10 cm above the ground.
• In late May you can shorten the stems by a third: the plant stays shorter and sturdier and flowers slightly later.
• You can also shorten only the front stems, so that the clump flowers in tiers.

Caution: Do not cut it back in autumn: the stems and seed heads protect the crown and give insects shelter.

Pruning: when and how · Pruning calendar and basic rules

Propagation

Division

In March–April, when the shoots are just emerging: cut pieces from the edge with a sharp spade. Old clumps are tough and woody.

Cuttings

In April–May, take 8–10 cm cuttings from young shoots and insert them in moist cutting compost.

Seed

Sow in autumn in a pot outdoors; the seed germinates after a cold spell.

Spotted Joe Pye weed: how does it get through the winter?

Hardy to −35 °C.

• Extremely hardy, to about −35 °C: in Belgium it needs no protection.
• The stems die but stay firmly upright: leave them until March.
• It is late to emerge, often not until April: mark the spot so you do not damage it when weeding or digging.
• In a large pot or container it overwinters outdoors; do not let the soil dry out, even in winter.

Diseases and pests

• Powdery mildew: White powder on the leaves in dry weather. Water and keep the soil moist with a mulch.
• Aphids: On young tips in spring. Hose them off; ladybirds help.
• Slugs: They eat the young shoots in April. Pick them off in the evening or protect the shoots with a collar.
• Brown lower leaves: A sign of drought. Water generously and mulch the soil.

Through the year

• March: Cut back old stems. Plant or divide. Add compost.
• April: The first shoots appear. Plant. Watch for slugs.
• May: In late May, cut back by a third if you wish. Take cuttings.
• June: Water in dry weather.
• July: Flowering begins. Butterflies on the flower heads.
• August: Full flower. Water generously in dry weather.
• September: Last flowers. Plant.
• October: Plant. Sow seed outdoors.
• December: Leave the stems and seed heads standing.

Good for wildlife

Bees

Nectar and pollen for honeybees and wild bees.

Butterflies

Nectar for butterflies.

Did you know?

• Maculatum means ‘spotted’: a reference to the purple spots on the stems.
• It used to be called Eupatorium maculatum and is related to our native hemp agrimony, which also attracts butterflies.
• The English name Joe Pye weed is said to refer to a man who used the plant; exactly who he was is not known for certain.