Symphyotrichum cordifolium
blue wood aster
A clump-forming perennial, up to 1.5m high, with upright, branching stems and oval to heart-shaped green leaves. Clusters of small daisy-like flowers, in pale violet, blue or occasionally white, are produced from late summer well into autumn
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Size
Ultimate height
1–1.5 metresTime to ultimate height
2–5 yearsUltimate spread
0.5–1 metresGrowing conditions
Moisture
Moist but well–drainedpH
Acid, Alkaline, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Green | |||
|---|---|---|---|---|
| Summer | Blue Purple White | Green | ||
| Autumn | Blue Purple White | Green | ||
| Winter |
Position
- Full sun
- Partial shade
Aspect
East–facing or South–facing or West–facing
Exposure
Exposed or Sheltered Hardiness
H7Botanical details
- Family
- Asteraceae
- Native to GB / Ireland
- No
- Foliage
- Deciduous
- Habit
- Clump forming
- Genus
Symphyotrichum includes around 90 species of annuals, biennials and perennials, mostly spread through the Americas, that were formerly included within the genus Aster. Leaves are simple, lance-shaped and entire, but it is their daisy-like flowerheads that they are grown for; central disc florets are typically yellow, surrounded by strap-shaped ray florets in shades of pink, blue, purple or white
- Name status
Correct
- Plant range
- USA
How to grow
Cultivation
Grow in fertile, moisture-retentive soil, in sun or part shade; add mulch after cutting back in autumn. Plants may need support, see staking: perennials. Divide every third year to retain vigour and flower quality. See aster cultivation
Propagation
Propagate by seed or by division in spring, replanting only vigorous young shoots
Suggested planting locations and garden types
- Cottage and informal garden
- Prairie planting
- Wildlife gardens
- Coastal
- Flower borders and beds
- Cut flowers
Pruning
Cut stems close to the ground in late autumn
Pests
May be susceptible to leaf and bud eelworm, aphids, slugs and snails
Diseases
May be susceptible to Fusarium wilt, powdery mildews, leaf spots and grey moulds
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