• 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

Phormium tenax

New Zealand flax

  • Other common names New Zealand flax
    common flax lily

    flax bush
    New Zealand hemp

    see more
  • Family Hemerocallidaceae

  • Genus Phormium are evergreen perennials, making a large clump of leathery, strap-shaped leaves, with tall panicles of small, tubular flowers in summer

  • Details P. tenax is a robust evergreen perennial making a medium-sized clump of dark grey-green, strap-shaped leaves. Tubular, dull red flowers about 4cm in length, in a panicle to 4m in height

  • Plant range New Zealand

Characteristics

  • Foliage Evergreen

  • Habit Clump-forming

  • 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

  • Partial Shade

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

  • Exposure Sheltered or Exposed

Soil

  • Chalk

    Loam

  • Chalk

    Sand

  • MoistureWell-drained, Moist but well-drained

  • SoilLoam, Sand

  • pHAcid, Neutral, Alkaline

Size

  • Ultimate height 2.5-4 metres

  • Ultimate spread 1.5-2.5 metres

  • Time to ultimate height 10-20 years

How to grow

Cultivation Grows best in fertile well-drained soil in full sun. May need protecting in northern climes

Propagation Propagate by seed sown in spring or by division in spring

Suggested planting locations and garden types Low Maintenance Flower borders and beds Architectural City & Courtyard Gardens Coastal Gravel Garden

How to care

Pruning Dead or damaged leaves may be removed in the spring

Pests Phormium mealybug may be a problem

Diseases Generally disease free

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