• 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

Libertia chilensis Formosa Group

New Zealand satin flower Formosa Group

New Zealand satin flower Formosa Group

© RHS

  • Other common names New Zealand satin flower Formosa Group

  • Synonyms Libertia formosa

  • Family Iridaceae

  • Genus Libertia are clump-forming perennials with grass-like, evergreen leaves and panicles of saucer-shaped white or blue flowers, followed by orange seed capsules

  • Details L. formosa is a robust evergreen plant forming a mass of narrowly sword-shaped, leathery leaves; bowl-shaped white flowers 3cm wide are borne in clusters on stiff stems in late spring and early summer

Characteristics

  • Foliage Evergreen

  • 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)

    H3

Colour

Sunlight

  • Full Sun

  • Aspect South-facing or West-facing

  • Exposure Sheltered

Soil

  • Clay

    Clay

  • Loam

    Loam

  • MoistureMoist but well-drained

  • SoilClay, Loam

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 0.5-1 metres

  • Ultimate spread 0.5-1 metres

  • Time to ultimate height 2-5 years

How to grow

Cultivation Grow in moderately fertile, moist but well drained soil in full sun. The foliage may be damaged in harsh winters

Propagation Propagate by seed; sow seeds in containers outdoors as soon as ripe. Divide in spring

Suggested planting locations and garden types Flower borders and beds Underplanting of Roses and Shrubs City & Courtyard Gardens Coastal Cottage & Informal Garden

How to care

Pruning Remove flower stalks after flowering. Trim back damaged foliage in spring

Pests Generally trouble free

Diseases Generally trouble free

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