• 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

Lupinus mutabilis

pearl lupin

  • Other common names pearl lupin
    tarhui

    tarwi

    see more
  • Family Fabaceae

  • Genus Lupinus can be annuals, perennials or shrubs, with palmate leaves and showy terminal racemes of pea-like flowers

  • Details L. mutabilis is an erect, bushy annual with blue-green leaves of seven to nine leaflets and upright spires of small, pea-like flowers with pale purple-blue keels, yellow standards and deep blue wings. The seeds can be processed to make them edible

Characteristics

  • Foliage Deciduous

  • Habit Bushy

  • Toxicity All parts, including unprocessed seeds, may cause severe discomfort if ingested

  • 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

  • Partial Shade

  • Full Sun

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

  • Exposure Exposed or Sheltered

Soil

  • Sand

    Sand

  • Loam

    Loam

  • MoistureMoist but well-drained

  • SoilSand, Loam

  • pHAcid, Neutral

Size

  • 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 in moderately fertile, humus-rich, light, moist but well-drained soil in full sun or light, dappled shade

Propagation Propagate from seed (indoors or outdoors)

Suggested planting locations and garden types Flower borders and beds Coastal Cottage & Informal Garden

How to care

Pruning Deadhead to encourage more flowers

Pests May be affected by slugs and lupin aphid

Diseases May be subject to powdery mildews, rots, a leaf spot and a virus

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