• 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

Asclepias tuberosa

butterfly flower

butterfly flower

© RHS

  • Other common names butterfly flower
    butterfly root

    butterfly weed
    chieger flower
    flux root
    Indian paintbrush
    Indian potato
    orange root
    pleurisy root
    swallow root
    tuber root
    white root
    wind root
    windward root

    see more
  • Family Apocynaceae

  • Genus Asclepias can be evergreen or deciduous perennials or subshrubs, with simple, entire leaves and umbel-like clusters of small, distinctively shaped flowers followed by paired fruits containing seeds embedded in silky fibres

  • Details A. tuberosa is a tuberous, hairy perennial with cymes of orange-red, sometimes orange or yellow flowers, from midsummer to early autumn, followed by fruit

  • Plant range USA

Characteristics

  • Foliage Deciduous

  • Habit Bushy

  • Toxicity All parts, particularly the roots, may cause mild stomach upset 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)

    H4

Colour

Sunlight

  • Full Sun

  • Aspect South-facing or West-facing

  • Exposure Sheltered

Soil

  • Sand

    Sand

  • Clay

    Clay

  • Loam

    Loam

  • MoistureWell-drained

  • SoilSand, Clay, Loam

  • pHAcid, Alkaline

Size

  • Ultimate height 0.5-1 metres

  • Ultimate spread 0.1-0.5 metres

  • Time to ultimate height 2-5 years

How to grow

Cultivation Grow outdoors in fertile well-drained loamy soil in full sun. Attractive to bees and ideal for a border or wildflower garden

Propagation Propagate by seed, propagate by division or root basal cuttings in spring

Suggested planting locations and garden types Flower borders and beds Cut Flowers Sub-tropical Wildflower meadow

How to care

Pruning No pruning required

Pests Generally pest free

Diseases Generally disease free

Did you find the information you were looking for?

RHS members can get exclusive individual advice from the RHS Gardening Advice team.

Join the RHS now

Get involved

We're a UK charity established to share the best in gardening. We want to enrich everyone's life through plants, and make the UK a greener and more beautiful place.