• 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 speciosa

bois chavanon

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
bois chavanon

© RHS

  • Other common names bois chavanon
    catawba

    cigar tree
    early-flowering catalpa
    hardy catalpa
    northern catalpa
    Indian cigar
    shawnee wood
    western catalpa

    see more
  • Synonyms Catalpa cordifolia

  • 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 C. speciosa is a tall, spreading tree with large, heart-shaped leaves. Large purple-spotted, white flowers sparsely borne in July, followed by long, slender seedpods

  • Plant range C. USA

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 South-facing or West-facing or East-facing

  • Exposure Sheltered

Soil

  • Chalk

    Chalk

  • Clay

    Clay

  • Sand

    Sand

  • Loam

    Loam

  • MoistureMoist but well-drained

  • SoilChalk, Clay, Sand, 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; will tolerate a heavy clay soil. 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 if grown pollarded

Pests Generally pest free

Diseases Susceptible to verticillium wilt

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