• 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

Lychnis flos-cuculi

ragged robin

  • Other common names ragged robin
    crow flower

    crow soap
    cuckoo flower
    cuckoo gilliflower
    cuckoo hood
    Indian pink
    marsh gilliflower
    meadow lychnis
    meadow pink
    wild William

    see more
  • Synonyms Silene flos-cuculi

  • Family Caryophyllaceae

  • Genus Lychnis can be biennials or perennials, with simple leaves and tubular, salver-shaped or star-shaped flowers in terminal clusters

  • Details L. flos-cuculi is an upright perennial to 70cm, with branched stems bearing opposite, lance-shaped leaves and, in late spring and early summer, terminal clusters of star-shaped deep rose-pink flowers, each petal deeply cut into 4 narrow segments

  • Plant range Eur. Cauc. Russia


  • Foliage Deciduous

  • Habit Columnar/Upright

  • 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)




  • Full Sun

  • Partial Shade

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

  • Exposure Sheltered or Exposed


  • Loam


  • Sand


  • Clay


  • MoistureMoist but well-drained

  • SoilLoam, Sand, Clay

  • pHAcid, Alkaline, Neutral


  • Ultimate height 0.5-1 metres

  • Ultimate spread 0.1-0.5 metres

  • Time to ultimate height 2-5 years

How to grow

Cultivation Thrives in a moist, moderately fertile soil in sun or part shade. Well suited to moist meadows or wild gardens

Propagation Propagate by seed, division or take basal cuttings

Suggested planting locations and garden types Flower borders and beds Wildlife Gardens Wildflower meadow Cottage & Informal Garden

How to care

Pruning Deadhead to prolong flowering

Pests Generally pest free

Diseases Generally disease free

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