• 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

Eupatorium maculatum Atropurpureum Group

eupatorium Atropurpureum Group

eupatorium Atropurpureum Group

© RHS 2002

  • Other common names eupatorium Atropurpureum Group

  • Synonyms Eupatorium atropurpureum misapplied
    Eupatorium fistulosum 'Atropurpureum'

    Eupatorium maculatum 'Atropurpureum'
    Eupatorium purpureum 'Atropurpureum'
    Eupatorium purpureum var. atropurpureum

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  • Family Asteraceae

  • Genus Eupatorium can be annuals, herbaceous perennials, subshrubs or evergreen shrubs, with small tubular flowers borne in terminal panicles or corymbs

  • Details Atropurpureum Group is a robust herbaceous perennial, to 2m in height, with whorled, oval leaves and erect purplish stems bearing flat, terminal clusters of small, tubular, deep rose-purple flowers in mid and late summer

Characteristics

  • Foliage Deciduous

  • Habit Clump-forming

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

  • Exposure Exposed or Sheltered

Soil

  • Chalk

    Chalk

  • Clay

    Clay

  • Sand

    Sand

  • Loam

    Loam

  • MoistureWell-drained, Moist but well-drained, Poorly-drained

  • SoilChalk, Clay, Sand, Loam

  • pHNeutral, Acid, Alkaline

Size

  • Ultimate height 1.5-2.5 metres

  • Ultimate spread 0.5-1 metres

  • Time to ultimate height 2-5 years

How to grow

Cultivation Grow in any moist soil in full sun or partial shade

Propagation Propagate by seed sown in containers in spring or autumn, or by division in spring

Suggested planting locations and garden types Flower borders and beds Cottage & Informal Garden Prairie Planting

How to care

Pruning Cut back at the end of the season

Pests Generally pest free

Diseases Generally disease free

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