• 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

Olsynium douglasii

grass widow

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
grass widow

© RHS

  • Other common names grass widow
    purple-eyed grass

    purple rush lily
    purple snowdrop
    spring bell
    spring satin flower

    see more
  • Synonyms Sisyrinchium douglasii
    Sisyrinchium grandiflorum

  • Family Iridaceae

  • Genus Olsynium are fibrous-rooted, clump-forming perennials. They have mostly basal, stem-clasping, linear or lance-shaped leaves and nodding trumpet to bell-shaped flowers in spring

  • Details O. douglasii produces slender, upright stems sheathed with grass-like leaves. The flowers are 2cm long, nodding, bell-shaped and a rich purple with a satiny texture. They appear in early spring

  • Plant range W Canada W USA

Characteristics

  • Foliage Deciduous

  • Habit Columnar/Upright

  • 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)

    H5

Colour

Sunlight

  • Partial Shade

  • Aspect North-facing or East-facing

  • Exposure Sheltered

Soil

  • Loam

    Loam

  • MoistureMoist but well-drained

  • SoilLoam

  • pHAcid, Neutral, Alkaline

Size

  • Ultimate height 0.1-0.5 metres

  • Ultimate spread 0-0.1 metre

  • Time to ultimate height 2-5 years

How to grow

Cultivation Grow in moist, humus-rich, moderately fertile soil in semi-shade

Propagation Propagate by seed sown in containers in a cold frame in autumn

Suggested planting locations and garden types Gravel Garden Patio & Container Plants Rock Garden

How to care

Pruning No pruning required

Pests Generally problem free

Diseases Generally problem free

Advertise here

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