About

Amsonia illustris is a perennial plant that develops into a compact clump over time. It features lanceolate, shiny leaves measuring between 3 and 7 centimeters, which transition to a vibrant golden-yellow hue in the fall. In late spring and early summer, upright stems support airy clusters of pale blue flowers, each reaching up to 1.5 centimeters in diameter.

About the genus

Amsonia consists of perennial plants that grow in clumps and produce a milky sap. They feature elongated, lanceolate leaves and bear clusters of small, star-like blue blooms at the tips during the spring and summer months.

Growing conditions

Sunlight
Full sun, Partial shade
Soil type
Chalk, Clay, Loam, Sand
Soil pH
Acid, Alkaline, Neutral
Soil moisture
Moist but well-drained
Aspect
East-facing, North-facing, South-facing, West-facing
Exposure
Exposed, Sheltered
UK hardiness
H5

Plant details

Plant type
Herbaceous Perennial
Habit
Clump forming
Foliage
Deciduous
Height
1-1.5 metres
Spread
0.1-0.5 metres
Time to full height
2-5 years
Suggested uses
City and courtyard gardens, Cottage and informal garden, Rock garden
Native to
C USA

Care notes

Cultivation
Grow in moist well-drained soil in full sun or light shade. Can tolerate periods of drought
Pruning
No pruning required
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
Pest resistance
Generally pest-free
Disease resistance
Generally disease-free