• AGM plants

    AGM plants have been through a rigourous 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

Crambe cordifolia

Flowering sea kale

AGM plants

AGM plants have been through a rigourous 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
Flowering sea kale

© � RHS 2002

  • Other common names Flowering sea kale
    Heart-leaved colewort

    Greater sea kale

    see more
  • Genus Crambe are robust annuals and perennials with large, simple or divided leaves and racemes or large panicles of small, fragrant white flowers

  • Family Brassicaceae / Brassicaceae

  • Species C. cordifolia is an herbaceous perennial to 1.8m in height, with bold, dark green, lobed leaves to 30cm in width, and branched sprays of small, scented white flowers

  • Plant range Caucasus

Characteristics

  • Foliage Deciduous

  • Habit Clump-forming

  • Fragrance Flower

  • 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)
    Old hardiness ratings

    While we update our systems with the new hardiness ratings you may still see old hardiness ratings in your search results. These are denoted as 'Old'.

    • H1 - Requires heated glass
    • H2 - Requires unheated glass
    • H3 - Hardy outside in some regions of the UK
    • H4 - Hardy throughout the UK
    • H1 + H3 - Requires heated glass but may be grown outside in summer

    For full details of the hardiness ratings see

    see more

    H5

Colour

Sunlight

  • Full Sun

  • Partial Shade

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

  • Exposure Sheltered

Soil

  • Chalk

    Loam

  • Chalk

    Chalk

  • Chalk

    Sand

  • MoistureWell-drained

  • SoilLoam, Chalk, Sand

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height

    1.5-2.5 metres

  • Ultimate spread

    1-1.5 metres

  • Time to ultimate height

    2-5 years

How to grow

Cultivation Ideally grow in a deep, fertile, well-drained soil in full sun although it will tolerate poor soil and partial shade. Provide shelter from strong winds.

Propagation Propagate by seed sown in pots in a cold frame in spring or autumn or propagate by division in early spring or take root cuttings in winter

Suggested planting locations and garden types Flower borders and beds Cut Flowers Architectural Cottage & Informal Garden Wildlife Gardens

How to care

Pruning Cut down to ground level in autumn

Pests Can get flea beetles, slugs and caterpillars

Diseases May suffer from club root

Advertise here