• 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

Kalmia polifolia

bog kalmia

  • Other common names bog kalmia
    bog laurel

    swamp laurel
    eastern bog laurel

    see more
  • Synonyms Kalmia glauca

  • Family Ericaceae

  • Genus Kalmia are evergreen shrubs with simple, leathery leaves and racemes or corymbs of bowl-shaped flowers in spring or summer

  • Details A small, evergreen shrub growing to a height of 60cm, with sparse branches and thin, glossy, gark green leaves. In mid and late spring, purple-pink saucer shaped flowers are borne

  • Plant range N North America

Characteristics

  • Foliage Evergreen

  • Habit Clump-forming

  • Toxicity All parts can cause severe discomfort if eaten. Wear gloves and other protective equipment when handling

  • 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

  • Full sun

  • Partial shade

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

  • Exposure Exposed or Sheltered

Soil

  • Sand

    Sand

  • Loam

    Loam

  • Clay

    Clay

  • MoistureMoist but well-drained, Poorly-drained

  • SoilSand, Loam, Clay

  • pHAcid

Size

  • Ultimate height 0.5-1 metres

  • Ultimate spread 0.5-1 metres

  • Time to ultimate height 5-10 years

How to grow

Cultivation Grow in moist, acidic soil enriched with acidic organic matter such as leaf mould, in part shade. Sun is tolerated if the soil is kept moist in summer

Propagation Propagate by greenwood cuttings in summer, hardwood cuttings in midwinter, by seed in winter to early spring or by layering in spring

Suggested planting locations and garden types Flower borders and beds Low Maintenance Wall-side Borders Cottage & Informal Garden

How to care

Pruning Pruning group 8

Pests Generally pest-free

Diseases Generally disease-free

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