• 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

Brugmansia arborea 'Knightii' (d)

angel's trumpet 'Knightii'

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
angel's trumpet 'Knightii'

© RHS 2002

  • Other common names angel's trumpet 'Knightii'

  • Synonyms Brugmansia × candida 'Knightii'
    Brugmansia × candida 'Plena'

    Brugmansia 'Knightii'

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  • Family Solanaceae

  • Genus Brugmansia are large evergreen shrubs with simple, ovate leaves and large, solitary, pendent trumpet-shaped or tubular flowers which are often fragrant

  • Details 'Knightii' is an evergreen shrub or small tree to 4m in height or more, with large elliptic leaves and pendulous, fragrant, hose-in-hose double, white flowers to 30cm in length

Characteristics

  • Foliage Evergreen

  • Habit Bushy

  • Fragrance Flower

  • Toxicity All parts are highly toxic if ingested

  • 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)

    H1C

Colour

Sunlight

  • Full Sun

  • Aspect South-facing or West-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 2.5-4 metres

  • Ultimate spread 1.5-2.5 metres

  • Time to ultimate height 10-20 years

How to grow

Cultivation Grow outdoors in full sun in frost-free area in moist but well-drained soil. Grow under glass in loam-based potting compost in full light

Propagation Propagate by seed or semi-hardwood cuttings

Suggested planting locations and garden types Drought Resistant Flower borders and beds City & Courtyard Gardens Cottage & Informal Garden Patio & Container Plants

How to care

Pruning Pruning group 9

Pests Can get glasshouse red spider mite, glasshouse whitefly, thrips and mealybugs under glass

Diseases Generally disease free

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