• 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

Persicaria bistorta

common bistort

common bistort

© RHS 1999

  • Other common names common bistort
    adderwort

    dragonwort
    Easter giant
    Easter ledges
    Easter magiant
    Easter man-giant
    gentle dock
    great bistort
    osterick
    oysterloit
    passion dock
    patience dock
    patient dock
    red legs
    snakeweed
    twice-writhen

    see more
  • Family Polygonaceae

  • Genus Persicaria can be annuals, herbaceous or evergreen perennials or sub-shrubs with simple leaves and small bell-shaped white or pink flowers in long-lasting spikes or panicles

  • Details P. bistorta is a vigorous rhizomatous perennial to 1m tall, with prominently veined, ovate leaves to 30cm long, and dense spikes of small pale pink flowers in summer and early autumn

  • Plant range Europe, N & W Asia

Characteristics

  • Foliage Semi-evergreen

  • 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

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

  • Exposure Exposed or Sheltered

Soil

  • Sand

    Sand

  • Clay

    Clay

  • Chalk

    Chalk

  • Loam

    Loam

  • MoisturePoorly-drained, Moist but well-drained

  • SoilSand, Clay, Chalk, Loam

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 0.5-1 metres

  • Ultimate spread 0.5-1 metres

  • Time to ultimate height 2-5 years

How to grow

Cultivation Ideal for a moist soil although it can tolerate some dryness; copes in full sun or partial shade

Propagation Propagate by division in spring or autumn

Suggested planting locations and garden types Flower borders and beds Cottage & Informal Garden

How to care

Pruning Deadhead faded spikes

Pests Generally pest free

Diseases Generally disease free

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