• 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

Alisma plantago-aquatica

water plantain

  • Other common names water plantain
    deil's spoons

    devil's spoons
    mad dog weed

    see more
  • Synonyms Alisma plantago

  • Family Alismataceae

  • Genus Alisma are rhizomatous herbaceous perennials from wet habitats, with basal rosettes of long-stalked, elliptic leaves and open panicles of small white or pink flowers in spring

  • Details A. plantago-aquatica is an aquatic perennial forming rosettes of grey-green leaves to 30cm in length, with tall panicles of white flowers to 1.5cm across in late spring


  • Foliage Deciduous

  • Habit Tufted

  • 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

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

  • Exposure Sheltered or Exposed


  • Sand


  • Loam


  • Clay


  • MoisturePoorly-drained

  • SoilSand, Loam, Clay

  • pHAlkaline, Neutral, Acid


  • Ultimate height 0.5-1 metres

  • Ultimate spread 0.1-0.5 metres

  • Time to ultimate height 2-5 years

How to grow

Cultivation Grow at pond margins in water up to 30cm deep. Deadhead regularly in order to prevent problems from self-seeding

Propagation Propagate by seed sown as soon as ripe or by rhizome division in spring

Suggested planting locations and garden types Cottage & Informal Garden Wildlife Gardens

How to care

Pruning Deadhead regularly in order to prevent problems from self-seeding

Pests Generally pest free

Diseases Generally disease free

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