• 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 purpureum

gravel root

  • Other common names gravel root
    grass root

    gravel weed
    hardy ageratum
    Indian gravel root
    Indian sage
    Indian sanicle
    Joe Pye weed
    kidney root
    kidney wort
    marsh milkweed
    motherwort
    pride of the meadow
    purple boneset
    purple hemp agrimony
    queen of the meadow
    queen of the prairie
    quill wort
    sisters of healing
    skunkweed
    trumpet weed
    sweet-scented joe-pyeweed

    see more
  • Family Asteraceae

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

  • Details E. purpureum is a clump-forming perennial with lance-shaped, sometimes purple-tinged leaves to 25cm long, and domed clusters of small, purplish-pink flowers in late summer and early autumn

  • Plant range E North America

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 South-facing or West-facing or East-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 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 City & Courtyard Gardens Coastal Cottage & Informal Garden

How to care

Pruning Cut back at the end of the season

Pests Generally pest free

Diseases Generally disease free

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