New England aster

New England aster: how do you recognise it?

Habit

A tall, upright clump up to 1.5 m high and about 80 cm wide.

Stem

Sturdy and hairy, branching at the top.

Leaves

Narrow and lance-shaped, rough and hairy; the base of the leaf clasps the stem.

Flower

Clusters of flowers about 3–4 cm across, with many narrow rays around a yellow centre.

Colour

Purple, violet, pink, pinkish red or white, depending on the variety.

Roots

A compact, woody rootstock that widens slowly.

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

Why grow it?

• Late flowers, from August to October, as the rest of the garden winds down.
• A top plant for butterflies, bees and bumblebees in autumn.
• Little troubled by powdery mildew, unlike many other autumn asters.
• Tall and sturdy: a fine backdrop for a border or a prairie-style garden.
• A good cut flower for autumn bouquets.

New England aster: where does it grow best?

• Full sun: in shade the stems go floppy and it flowers less.
• Fertile sandy, loamy or clay soil; acid, neutral or chalky.
• Normal to moist: the soil must not dry out in summer, or the lower leaves turn brown.
• At the back of the border or in a prairie planting; put lower plants in front to hide the bare base.
• Allow 60–80 cm between plants.

Light

Sun

Soil type

Sand, loam or clay

Acidity

Not fussy

Moisture

Normal or wet

Size

1.5 m tall, 0.8 m wide

Hardiness

Hardy (to -35 °C)

Goes well with

• Japanese anemone: White or pink flowers that open at the same time.
• Ornamental grasses: Tall grasses such as miscanthus together create a prairie feel.
• Coneflower: Comes from the same American prairies and is also loved by butterflies.
• Orpine: Lower pink flower heads in front of the aster’s bare base.

New England aster: when and how to plant it?

Plant in March–May.

1. Plant in March, April or May.
2. Dig a generous hole and mix in compost.
3. Set the plant at the same depth as in the pot and firm the soil.
4. Space plants 60–80 cm apart so air can move between them.
5. Water well straight away and in dry spells during the first year.
6. Mulch with compost or leaf mould to hold in moisture.

Care

Watering

Water generously in dry summers: drought turns the lower leaves brown.

Feeding

A layer of compost in spring.

Pinching back

At the end of May, cut the stems back by a third for a shorter, sturdier plant.

Support

In a windy spot, support the tall stems with a ring or canes.

Dividing

Every three to four years in spring.

Tip: At the end of May, cut the stems back by a third: the plant stays shorter and sturdier and needs less support. Put lower plants in front to hide the bare base.

New England aster: when to prune it?

Pruning months: March and May.

When: Cut the old stems down in March, and cut the new stems back by a third at the end of May.

How:

• In March, cut the old stems down to just above the ground.
• At the end of May, cut all stems back by a third: the plant stays shorter, branches more and needs less support.
• If you cut back only some of the stems, you spread the flowering.
• Leave the spent stems standing over winter.

Caution: Do not cut back after mid-June, or you will lose flowers.

Pruning: when and how · Pruning calendar and basic rules

Propagation

Division

Every three to four years in March–April. Take young pieces from the edge and discard the old, woody centre.

Cuttings

In April–May, take basal cuttings from young shoots and root them in sandy compost.

New England aster: how does it get through the winter?

Hardy to −35 °C.

• Very hardy, to about −35 °C: no protection is needed.
• Leave the spent stems until March: they give structure and shelter for insects.
• In a large pot it stays hardy too; keep the pot in a sheltered spot.

Diseases and pests

• Bare base: It often loses its lower leaves, especially in drought. Watering and lower plants in front help.
• Falling over: Tall stems fall over after rain. Cut back at the end of May or support them.
• Slugs: They eat the young shoots in spring. Pick them off in the evening.
• Powdery mildew: Uncommon; in dry weather sometimes a little white powder. Watering and leaving space help.

Through the year

• March: Cut down old stems. Divide and plant.
• April: Plant. Add compost. Take cuttings.
• May: Plant. At the end of May, cut the stems back by a third.
• June: Put in supports. Water in dry spells.
• July: Water in dry spells.
• August: Flowering begins.
• September: Full flower: butterflies and bees. Cut flowers for the vase.
• October: Last flowers.
• November: Leave the stems standing for winter.

Good for wildlife

Bees

Nectar and pollen for honeybees and wild bees.

Butterflies

Nectar for butterflies.

Did you know?

• Botanists moved the American asters into the genus Symphyotrichum; that is why it is sometimes still sold as Aster novae-angliae.
• The name novae-angliae means ‘of New England’. Its cousin, the Michaelmas daisy (novi-belgii), is named after New Netherland, the Dutch colony around present-day New York.
• In North America it is an important nectar source for the monarch butterfly on its southward migration in autumn.