• 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

Triteleia laxa

grassnut

grassnut

© RHS 2002

  • Other common names grassnut
    triplet lily

    Ithuriel's spear

    see more
  • Synonyms Brodiaea candida
    Brodiaea laxa

  • Family Asparagaceae

  • Genus Triteleia are cormous perennials with linear basal leaves and umbels of funnel-shaped flowers opening as the leaves die down

  • Details T. laxa is a perennial with linear basal leaves and loose umbels of funnel-shaped, mid- to deep blue flowers 3-4cm in length, on stems to 50cm in early summer

  • Plant range NW USA

Characteristics

  • 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)

    H3

Colour

Sunlight

  • Full Sun

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

  • Exposure Sheltered

Soil

  • Loam

    Loam

  • Sand

    Sand

  • MoistureWell-drained

  • SoilLoam, Sand

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 0.1-0.5 metres

  • Ultimate spread 0-0.1 metre

  • Time to ultimate height 2-5 years

How to grow

Cultivation Plant 8cm deep in autumn in light, sandy, fertile soil. Will need protection from frosts and excessive winter wet

Propagation Propagate by seed, sown with moderate heat as soon as ripe. Separate corms when dormant

Suggested planting locations and garden types Flower borders and beds Cut Flowers City & Courtyard Gardens Cottage & Informal Garden Mediterranean Climate Plants

How to care

Pruning No pruning required

Pests Generally pest free

Diseases Generally disease free

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