Symphyotrichum puniceum
swamp aster
A clump-forming perennial, about 2m high, with strong upright, green to purplish stems and lance-shaped dark green leaves, tinted purple in autumn. Clusters of small daisy-like flowers, in pale lavender-blue with a yellow centre, are produced from late summer well into autumn
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Size
Ultimate height
1.5–2.5 metresTime to ultimate height
2–5 yearsUltimate spread
0.5–1 metresGrowing conditions
Moisture
Moist but well–drained, Well–drainedpH
Acid, Alkaline, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Green | |||
|---|---|---|---|---|
| Summer | Purple Blue | Green | ||
| Autumn | Purple Blue | Green Purple | ||
| 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
How to grow
Cultivation
Grow in moderately fertile, moist but well-drained soil in full sun or light shade. Stake tall plants in early spring, see staking perennials. See aster cultivation for further advice
Propagation
Propagate by division in spring or root softwood basal cuttings in spring; division can be carried out every third year to maintain vigour
Suggested planting locations and garden types
- Coastal
- Cottage and informal garden
- Gravel garden
- Prairie planting
- Wildlife gardens
- Cut flowers
- Flower borders and beds
Pruning
Cut stems close to the ground in late autumn
Pests
May be susceptible to leaf and bud eelworms, slugs and snails
Diseases
May be susceptible to Verticillium wilt, powdery mildews and grey moulds
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