• 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

Cardamine trifolia

three-leaved cuckoo flower

three-leaved cuckoo flower

© RHS

  • Other common names three-leaved cuckoo flower
    trefoil cress

  • Family Brassicaceae

  • Genus Cardamine are herbaceous perennials with simple, palmately or pinnately divided leaves and short racemes of 4-petalled white, yellow, pink or purplish flowers in spring or summer

  • Details C. trifolia is a creeping perennial with three-lobed, dark green leaves. In late spring it produces clusters of open, cup-shaped, white flowers on 15cm stems

  • Plant range C & S Europe

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)

    H5

Colour

Sunlight

  • Full Shade

  • Partial Shade

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

  • Exposure Sheltered

Soil

  • Chalk

    Chalk

  • Clay

    Clay

  • Sand

    Sand

  • Loam

    Loam

  • MoisturePoorly-drained

  • SoilChalk, Clay, Sand, Loam

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 0.1-0.5 metres

  • Ultimate spread 0.1-0.5 metres

  • Time to ultimate height 2-5 years

How to grow

Cultivation Grow in humus-rich, moist soil in full or partial shade

Propagation Propagate by seed or division

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

How to care

Pruning No pruning required

Pests Can get aphids and flea beetles

Diseases Generally disease free

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