• 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

Calluna vulgaris 'Mullion'

heather 'Mullion'

heather 'Mullion'


  • Other common names heather 'Mullion'

  • Family Ericaceae

  • Genus Calluna are low-growing or dwarf evergreen shrubs with stems clothed in tiny overlapping leaves, and terminal, spike-like racemes of small, 4-petalled flowers with coloured calyces

  • Details 'Mullion' is a low, spreading evergreen shrub to 20cm tall, with very compact, prostrate, mid-green foliage and short spikes of deep mauve-pink flowers


  • Foliage Evergreen

  • Habit Mat 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)




  • Full Sun

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

  • Exposure Exposed or Sheltered


  • Chalk


  • Chalk


  • Chalk


  • MoistureWell-drained, Moist but well-drained

  • SoilSand, Clay, Loam

  • pHAcid


  • 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 well-drained acidic soil in full sun

Propagation Propagate by semi-hardwood cuttings

Suggested planting locations and garden types Banks and Slopes Flower borders and beds Ground Cover City & Courtyard Gardens Coastal Cottage & Informal Garden Patio & Container Plants Rock Garden

How to care

Pruning Pruning group 10

Pests Generally pest free

Diseases May be subject to fungal diseases

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