• 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

Trillium erectum

birthroot

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
birthroot

© � RHS

  • Other common names birthroot
    American shamrock

    bathroot
    bethroot
    bloody nose
    bumblebee root
    death root
    dog flower
    ground lily
    herb Paris
    Indian balm
    lamb's quarters
    lamb's succory
    nosebleed
    orange blossoms
    red Benjamin
    squawroot
    stinking Benjamin
    true love

    see more
  • Genus Trillium are rhizomatous, herbaceous perennials with erect stems bearing a whorl of ovate or diamond-shaped leaves, with one or more erect or nodding flowers borne at the stem apex

  • Family Melanthiaceae / Melanthiaceae

  • Details T. erectum is a perennial to 50cm in height, with erect stems each bearing a whorl of three broadly ovate leaves and a solitary, terminal, nodding deep maroon, occasionally white, flowers 5-9cm across in spring

  • Plant range E North America

Characteristics

  • Foliage Deciduous

  • Habit Columnar/Upright

  • Toxicity

  • 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)
    Old hardiness ratings

    While we update our systems with the new hardiness ratings you may still see old hardiness ratings in your search results. These are denoted as 'Old'.

    • H1 - Requires heated glass
    • H2 - Requires unheated glass
    • H3 - Hardy outside in some regions of the UK
    • H4 - Hardy throughout the UK
    • H1 + H3 - Requires heated glass but may be grown outside in summer

    For full details of the hardiness ratings see

    see more

    H5

Colour

Sunlight

  • Partial Shade

  • Full Shade

  • Aspect North-facing or East-facing or West-facing

  • Exposure Sheltered

Soil

  • Chalk

    Sand

  • Chalk

    Loam

  • Chalk

    Chalk

  • MoistureMoist but well-drained

  • SoilSand, Loam, Chalk

  • pHAcid, Neutral

Size

  • Ultimate height

    0.1-0.5 metres

  • Ultimate spread

    0.1-0.5 metres

  • Time to ultimate height

    2-5 years

How to grow

Cultivation Grow in deep, moist but well-drained, humus-rich, preferably acid to neutral soil in deep or partial shade. Mulch in autumn with leaf mould

Propagation Propagate by seed in pots in a shady cold frame as soon as seed is ripe; takes 5-7 years to reach flowering size. Propagate rhizomes by division after flowering or cut out the growing point from the rhizome after flowering, which stimulates the formation

Suggested planting locations and garden types Flower borders and beds Underplanting of Roses and Shrubs

How to care

Pruning No pruning required

Pests Slugs and snails may be a problem

Diseases Generally disease free

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