• AGM plants

    AGM plants have been through a rigorous trial and assessment programme. They are:

    • Excellent for ordinary use in appropriate conditions
    • Available to buy
    • Of good constitution
    • Essentially stable in form & colour
    • Reasonably resistant to pests & diseases

Amsonia tabernaemontana var. salicifolia

eastern bluestar

  • Other common names eastern bluestar

  • Synonyms Amsonia salicifolia

  • Family Apocynaceae

  • Genus Amsonia are clump-forming perennials with milky sap, lance-shaped leaves and terminal panicles of small, starry blue flowers in spring and summer

  • Details A. tabernaemontana var. salicifolia is a clump-forming perennial to 60cm with dark green, willow-like leaves and open clusters of star-shaped, pale blue flowers from late spring to midsummer

  • Plant range S & E North America

Characteristics

  • Foliage Deciduous

  • Habit Clump-forming

  • Toxicity Contact with milky sap may irritate skin

  • Hardiness

    Hardiness ratings

    All ratings refer to the UK growing conditions unless otherwise stated. Minimum temperature ranges (in degrees C) are shown in brackets

    • H1a - Under glass all year (>15C)
    • H1b - Can be grown outside in the summer (10 - 15)
    • H1c - Can be grown outside in the summer (5 - 10)
    • H2 - Tolerant of low temperatures, but not surviving being frozen (1 to 5)
    • H3 - Hardy in coastal and relatively mild parts of the UK (-5 to 1)
    • H4 - Hardy through most of the UK (-10 to -5)
    • H5 - Hardy in most places throughout the UK even in severe winters (-15 to -10)
    • H6 - Hardy in all of UK and northern Europe (-20 to -15)
    • H7 - Hardy in the severest European continental climates (< -20)

    H5

Colour

Sunlight

  • Full Sun

  • Partial Shade

  • Aspect South-facing or East-facing or West-facing

  • Exposure Exposed or Sheltered

Soil

  • Loam

    Loam

  • Chalk

    Chalk

  • Sand

    Sand

  • Clay

    Clay

  • MoistureMoist but well-drained

  • SoilLoam, Chalk, Sand, Clay

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 0.5-1 metres

  • Ultimate spread 0.1-0.5 metres

  • Time to ultimate height 2-5 years

How to grow

Cultivation Grows best in a fertile, moist but well-drained soil in full sun, although it can tolerate partial shade and is fairly drought-tolerant

Propagation Propagate by seed sown in pots in a cold frame in autumn or spring. Alternatively propagate by division in spring or root softwood cuttings in early summer

Suggested planting locations and garden types Flower borders and beds Drought Resistant Prairie Planting Cottage & Informal Garden

How to care

Pruning Cut back in late autumn

Pests Generally pest free

Diseases Generally disease free

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