New England aster

Sun

Full sun gives the strongest stems and most flowers; tolerates light shade but may become floppy.

Water

Moderate; keep the root zone evenly moist, especially while establishing and during dry summers.

Soil

Average to fertile, moisture-retentive soil with drainage; tolerates clay. Avoid very dry soil and prolonged waterlogging.

Height

3-6 ft (0.9-1.8 m)

Spread

2-3 ft (0.6-0.9 m)

Flowers

Late summer through autumn; usually violet-purple with yellow centres that darken with age. Pink, reddish-purple and white forms also occur.

Foliage

Deciduous, with narrow, rough, hairy green leaves that clasp the hairy stems. Lower leaves often dry out before flowering.

Growth

Fast; forms a substantial clump within a few growing seasons.

Care needed

Medium

• Water deeply during dry spells; drought often causes the lower leaves to brown.
• Apply a thin layer of compost in spring; avoid heavy nitrogen feeding, which encourages floppy growth.
• Mulch to conserve moisture, keeping mulch clear of the crown.
• Put supports around tall clumps in spring, before stems lean or flowers open.
• Divide congested clumps every 3-4 years in spring, retaining vigorous outer sections.

Pruning. For shorter, bushier plants, cut stems back by about one-third in late spring or early summer; flowering may be slightly later. Leave healthy stems standing through winter, then cut them to just above ground level in late winter or early spring.

Early spring

Cut down old stems before new shoots become tall.

Spring

Plant or divide clumps, water well, and add compost and mulch.

Late spring

Install supports; shorten stems by one-third if you want a more compact plant.

Summer

Water during dry spells and check lower leaves for mildew or rust.

Autumn

Remove fading flower heads before seed ripens if unwanted seedlings are a concern.

Winter

Leave healthy stems for shelter and structure; remove diseased material.

• Place at the back of a sunny border, with shorter perennials hiding the bare lower stems.
• Combine with goldenrod and ornamental grasses for a late-season meadow effect.
• Repeat clumps through a new-perennial planting to carry colour into autumn.
• Use in a sunny wildlife border where late flowers support bees and butterflies.

Garden styles it suits: Cottage garden, Native meadow, New perennial (prairie), Pollinator garden, Autumn colour and Midwest prairie.

Plant it with: Switchgrass, Little bluestem, Goldenrod, Black-eyed Susan, Sneezeweed and Purple coneflower.

Wildlife: Flowers provide late-season nectar and pollen for bees, butterflies and other insects. In its native North American range, the foliage also supports some moth and butterfly larvae; standing stems provide shelter for small invertebrates.

• Powdery mildew: white coating on leaves, especially in crowded or stressed plants. Improve spacing, water the soil during drought, and remove affected debris.
• Rust: orange or brown pustules on leaves. Remove badly affected foliage, avoid overhead watering, and clear infected debris.
• Flopping stems: often caused by shade, rich feeding or unsupported tall growth. Give full sun, avoid excess fertiliser, and stake early or shorten stems in late spring.
• Browning lower leaves: common as stems mature and worse in dry soil. Maintain moisture and place shorter plants in front to conceal bare stem bases.

Not known to be toxic to cats, dogs, horses or people; no part is recognised as a significant poisoning hazard. It is not a food plant, and eating substantial amounts of garden plant material can cause stomach upset.

• New York aster (Symphyotrichum novi-belgii)

  Usually has smoother stems and less hairy leaves. New England aster has conspicuously hairy stems and rough, hairy leaves with clasping bases.

• Smooth aster (Symphyotrichum laeve)

  Has smooth, often bluish-green leaves and stems rather than the rough, hairy foliage and stems of New England aster.

• Aromatic aster (Symphyotrichum oblongifolium)

  Usually forms a shorter, bushier mound with smaller leaves that smell aromatic when crushed; its leaves do not clasp the stems as those of New England aster do.

The species name novae-angliae means 'of New England', referring to the northeastern North American region.

Propagation. Divide in spring to keep a selected plant's characteristics. Take basal cuttings in spring, or sow seed in autumn or after a period of cold, moist treatment; seedlings from named cultivars may differ from the parent. Plants can self-seed if flower heads are left to ripen.

Accepted botanical name

Symphyotrichum novae-angliae

In the US and Canada

Native in Canada and the lower 48 states.

Native range

Alabama, Arkansas, Colorado, Connecticut, Delaware, District of Columbia, Georgia, Illinois, Indiana, Iowa, Kansas and Kentucky.

Measured

Soil pH 7 to 7.5. Average height 104 cm.

Sources: GBIF (CC BY 4.0), USDA PLANTS and Trefle (CC BY 4.0). The care and design notes are LandscapeGPT's own.