• 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

Astilbe koreana

Korean astilbe

Korean astilbe

© Henry Noblett

  • Other common names Korean astilbe

  • Family Saxifragaceae

  • Genus Astilbe are rhizomatous herbaceous perennials with attractive, usually ternately divided leaves and erect plume-like panicles of tiny white, pink or purple flowers in summer. The old, brown flower-heads remain attractive in autumn

  • Details A. koreana is a herbaceous perennial with bright green, divided leaves and plumes of creamy-white, or pale pink flowers up to 60cm tall in summer

  • Plant range China, Korea

Characteristics

  • Foliage Deciduous

  • Habit Bushy

  • 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)

    H7

Colour

Sunlight

  • Full Sun

  • Partial Shade

  • Full Shade

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

  • Exposure Exposed or Sheltered

Soil

  • Sand

    Sand

  • Clay

    Clay

  • Loam

    Loam

  • MoistureWell-drained, Moist but well-drained

  • SoilSand, Clay, Loam

  • pHNeutral, Acid, Alkaline

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 Will thrive in moist, fertile, humus-rich soil in full sun or partial shade, but will also tolerate full shade and drier conditions

Propagation Propagate by division in late winter or early spring, pot divisions under glass and plant out in late spring. Can also propagate by seed

Suggested planting locations and garden types Flower borders and beds Underplanting of Roses and Shrubs Cottage & Informal Garden

How to care

Pruning Cut back after flowering

Pests Generally pest free

Diseases Powdery mildews may be troublesome

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