Amsonia illustris

RHS Plant Profile
Ozark bluestar

Other common names

shining bluestar

Herbaceous Perennial

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

Position

Full sun, Partial shade

Soil Types

Chalk, Clay, Loam, Sand

Max Height

1-1.5 metres

Max Spread

0.1-0.5 metres

Size

Time to Maturity
2–5 years
Max Spread
0.1-0.5 metres
Max Height
1-1.5 metres

Growing Conditions

Chalk Clay Loam Sand
Moisture
Moist but well–drained
pH
Acid or Alkaline or Neutral

Position

Full sun Partial shade
Aspect
East–facing or North–facing or South–facing or West–facing
Exposure
Exposed or Sheltered
Hardiness
H5
Drought Resistance
Yes

Colour & Scent

Season Stem Flower Foliage Fruit
Spring
Summer
Autumn
Winter

Botanical 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