• 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

Hydrocharis morsus-ranae

frogbit

frogbit

© RHS 2002

  • Other common names frogbit

  • Family Hydrocharitaceae

  • Genus Hydrocharis can be submerged or floating aquatic perennials with glossy, rounded leaves and white, 3-petalled flowers in summer

  • Details H. morsus-ranae is a floating aquatic perennial with rounded leaves 3cm across, and white flowers 2-3cm across, with a yellow spot on each petal

Characteristics

  • Foliage Deciduous

  • Habit Floating

  • 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

  • Aspect South-facing or West-facing

  • Exposure Sheltered or Exposed

Soil

  • Sand

    Sand

  • Clay

    Clay

  • Loam

    Loam

  • Chalk

    Chalk

  • MoisturePoorly-drained

  • SoilSand, Clay, Loam, Chalk

  • pHAlkaline

Size

  • Ultimate height Up to 10 cm

  • Ultimate spread 0.5-1 metres

  • Time to ultimate height 5-10 years

How to grow

Cultivation Grow in still, alkaline water in full sun. Water must be deep enough to prevent bottom freezing to protect overwintering buds

Propagation Propagate by seed or division of stolons

Suggested planting locations and garden types Low Maintenance

How to care

Pruning No pruning required

Pests Leaves may be eaten by water snails, liable to attack by the larvae of the brown china-mark moth

Diseases Generally disease free

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