Amsonia illustris
Ozark bluestar
A slow-growing, clump-forming perennial bearing lance-shaped, glossy, bright green leaves, 3-7cm long, which turn golden-yellow in autumn. Open panicles of light blue flowers, to 1.5cm across, are produced on upright stems in late spring and early summer
Size
Ultimate height
1–1.5 metresTime to ultimate height
2–5 yearsUltimate spread
0.1–0.5 metresGrowing conditions
Moisture
Moist but well–drainedpH
Acid, Alkaline, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Green | |||
|---|---|---|---|---|
| Summer | Blue | Green | ||
| Autumn | Gold Yellow | |||
| Winter |
Position
- Full sun
- Partial shade
Aspect
East–facing or North–facing or South–facing or West–facing
Exposure
Exposed or ShelteredDrought resistance
Yes Hardiness
H5Botanical details
- Family
- Apocynaceae
- Native to GB / Ireland
- No
- Foliage
- Deciduous
- Habit
- Clump forming
- Genus
Amsonia are clump-forming perennials with milky sap, lance-shaped leaves and terminal panicles of small, starry blue flowers in spring and summer
- Name status
Correct
- Plant range
- C USA
How to grow
Cultivation
Grow in moist well-drained soil in full sun or light shade. Can tolerate periods of drought
Propagation
Propagate by seed sown in containers in a cold frame in autumn or spring. Divide in spring or early autumn. Root softwood or basal cuttings in early summer
Suggested planting locations and garden types
- City and courtyard gardens
- Cottage and informal garden
- Rock garden
- Flower borders and beds
Pruning
No pruning required
Pests
Generally pest-free
Diseases
Generally disease-free
Get involved
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