• 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 officinalis

pale butterfly bush

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
pale butterfly bush

© RHS

  • Other common names pale butterfly bush

  • 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. officinalis is a medium to large, semi-evergreen shrub with pale mauve, yellow-eyed, strongly fragrant flowers through winter into early spring. Leaves are dark green and strongly felted grey-white beneath with some sparser hairs on the upper surface too at times

  • Plant range W China

Characteristics

  • Foliage Semi-evergreen

  • 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)

    H3

Colour

Sunlight

  • Full Sun

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

  • Exposure Sheltered

Soil

  • Sand

    Sand

  • Chalk

    Chalk

  • Loam

    Loam

  • MoistureWell-drained

  • SoilSand, Chalk, Loam

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 2.5-4 metres

  • Ultimate spread 2.5-4 metres

  • Time to ultimate height 2-5 years

How to grow

Cultivation Under glass grow in a well-drained loam-based compost (JI No. 3) in full light and with good ventilation. Water freely when in growth but more sparingly in winter. Can be grown on a warm, sheltered wall in particularly mild locations

Propagation Root semi-ripe cuttings in summer

Suggested planting locations and garden types Patio & Container Plants

How to care

Pruning Prune back to a framework in spring; pruning group 6

Pests Susceptible to capsid bug, caterpillars, figwort weevil, mullein moth and glasshouse red spider mite

Diseases Generally trouble free

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