• 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

Pleione formosana

windowsill orchid

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
  • Other common names windowsill orchid

  • Genus Pleione are deciduous orchids with pseudobulbs each bearing one or two lance-shaped leaves and mostly solitary flowers to 8cm across, on short stems

  • Family Orchidaceae / Orchidaceae

  • Details P. formosana is a deciduous perennial to 15cm in height, with globose pseudobulbs, each bearing a single lance-shaped leaf and solitary pale or rose-pink flowers 8cm in width, the lip blotched with red or brown

  • Plant range SE China N & C Taiwan

Characteristics

  • Foliage Deciduous

  • Habit Clump-forming

  • 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

    H3

Colour

Sunlight

  • Partial Shade

  • Aspect West-facing or East-facing

  • Exposure Sheltered

Soil

  • Chalk

    Loam

  • Chalk

    Sand

  • MoistureWell-drained

  • SoilLoam, Sand

  • pHAcid, Neutral

Size

  • Ultimate height

    0.1-0.5 metres

  • Ultimate spread

    0.1-0.5 metres

  • Time to ultimate height

    5-10 years

How to grow

Cultivation Plant in mid-spring. Grow in sharply drained, moderately fertile, leafy, humus-rich soil in a sheltered spot in partial shade. In cold areas, protect from severe weather and winter wet. Can be grown in a shallow container indoors in a cool place. Only water when new growth appears

Propagation Propagate by division of pseudobulbs

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

How to care

Pruning No pruning required

Pests Aphids, glasshouse red spider mite, slugs and mealybugs may be a problem

Diseases Generally disease free

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