• 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

Rudbeckia amplexicaulis

clasping coneflower

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 clasping coneflower

  • Synonyms Dracopsis amplexicaulis

  • Family Asteraceae

  • Genus Rudbeckia may be annuals, biennials or rhizomatous herbaceous perennials, with simple or pinnately divided leaves and large daisy-like flower-heads with yellow or orange rays surrounding a prominent conical disk

  • Details R. amplexicaulis is an erect annual with ovate, stem-clasping leaves and solitary yellow flowers 5-7cm across in late summer and early autumn, the large central disk brown

Characteristics

  • Foliage Deciduous

  • Habit Bushy

  • 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)

    H7

Colour

Sunlight

  • Full Sun

  • Partial Shade

  • Aspect East-facing or South-facing

  • Exposure Exposed or Sheltered

Soil

  • Chalk

    Chalk

  • Clay

    Clay

  • Loam

    Loam

  • MoistureMoist but well-drained

  • SoilChalk, Clay, Loam

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 0.5-1 metres

  • Ultimate spread 0.1-0.5 metres

  • Time to ultimate height 1-2 years

How to grow

Cultivation Grow in moderately fertile heavy, moist but well-drained soil that does not dry out, in full sun or partial shade

Propagation Propagate by seed sown at 16-18°C in early spring

Suggested planting locations and garden types Cut Flowers Flower borders and beds Cottage & Informal Garden Prairie Planting City & Courtyard Gardens Coastal Wildlife Gardens

How to care

Pruning Cut back after flowering

Pests Slugs may damage young growth

Diseases Generally disease free

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