• 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

Catalpa × erubescens 'Purpurea'

purple hybrid catalpa

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 purple hybrid catalpa
    hybrid catalpa 'Purpurea'

  • Synonyms Catalpa bignonioides 'Purpurea'

  • Family Bignoniaceae

  • Genus Catalpa are deciduous trees of spreading habit, with handsome, large leaves and erect panicles of showy, bell-shaped flowers in late summer, followed by persistent, slender bean-like seed capsules

  • Details 'Purpurea' is a medium-sized deciduous tree. Young shoots and opening leaves blackish-purple, the leaves later dark green. Flowers 3cm, white with orange and purple markings, in large open panicle

Characteristics

  • Foliage Deciduous

  • Habit Spreading / Branched

  • 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)

    H6

Colour

Sunlight

  • Full Sun

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

  • Exposure Sheltered

Soil

  • Sand

    Sand

  • Chalk

    Chalk

  • Loam

    Loam

  • MoistureMoist but well-drained

  • SoilSand, Chalk, Loam

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height Higher than 12 metres

  • Ultimate spread wider than 8 metres

  • Time to ultimate height 20-50 years

How to grow

Cultivation Grow in a moist but well-drained, fertile soil in a sunny position. Shelter from strong winds as these may shred the large leaves. Protect from late spring frosts when young

Propagation Propagate by softwood cuttings or grafting

Suggested planting locations and garden types Architectural

How to care

Pruning Pruning group 1, or pruning group 7 when grown as a stooled shrub for foliage effect

Pests Generally pest free

Diseases Susceptible to verticillium wilt

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