• 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 Purpureum Group

New Zealand flax Purpureum Group

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
  • Other common names New Zealand flax Purpureum Group

  • Synonyms Phormium tenax 'Purpureum'
    Phormium tenax 'Atropurpureum'

    Phormium atropurpureum

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  • 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 Purpureum Group is a robust evergreen perennial with dull coppery-purple, strap-shaped leaves to 2m in length. Flowers reddish, in large panicles to 3m or taller

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 West-facing or South-facing or North-facing or East-facing

  • Exposure Exposed or Sheltered

Soil

  • Sand

    Sand

  • Loam

    Loam

  • MoistureWell-drained, Moist but well-drained

  • SoilSand, Loam

  • pHAlkaline, Acid, Neutral

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 Flower borders and beds Low Maintenance Gravel Garden Architectural City & Courtyard Gardens Coastal

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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