• 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

Buddleja davidii

butterfly bush

  • Other common names butterfly bush
    summer lilac

    orange eye

    see more
  • Synonyms Buddleja variabilis

  • Family Scrophulariaceae

  • Genus Buddleja can be evergreen or deciduous shrubs, occasionally trees or scrambling climbers with simple leaves and panicles of small, tubular fragrant flowers

  • Details B. davidii is a large, fast-growing, deciduous shrub, to 3m tall, with long, arching shoots and lance-shaped, pointed, green or grey-green leaves up to 25cm long. From summer to autumn it bears dense sprays, 30cm or more long, of small, fragrant flowers in various shades of purple

  • Plant range China & Japan

Characteristics

  • Foliage Deciduous

  • Habit Bushy

  • Fragrance Flower

  • 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

  • Partial Shade

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

  • Exposure Exposed or Sheltered

Soil

  • Sand

    Sand

  • Clay

    Clay

  • Chalk

    Chalk

  • Loam

    Loam

  • MoistureWell-drained, Moist but well-drained

  • SoilSand, Clay, Chalk, Loam

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 2.5-4 metres

  • Ultimate spread 4-8 metres

  • Time to ultimate height 5-10 years

How to grow

Cultivation Grow in well-drained soil in full sun or partial shade

Propagation Propagate semi-ripe cuttings in summer or hardwood cuttings in autumn

Suggested planting locations and garden types Flower borders and beds Wall-side Borders Drought Resistant City & Courtyard Gardens Coastal Cottage & Informal Garden

How to care

Pruning Pruning group 6

Pests May be attacked by capsid bug, caterpillars and glasshouse red spider mite

Diseases Generally disease free

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