• 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

Helianthemum nummularium

common rockrose

  • Other common names common rockrose
    flower of the sun

  • Synonyms Helianthemum nummularium 'Rock Mixed'
    Cistus helianthemum

    Helianthemum vulgare
    Helianthemum chamaecistus

    see more
  • Family Cistaceae

  • Genus Helianthemum are bushy or spreading evergreen shrubs with small paired leaves and saucer-shaped flowers borne in short racemes in spring and early summer

  • Details H. nummularium is a low, spreading evergreen shrub with tiny, oval leaves and sulphur yellow flowers produced from late spring to early autumn

  • Plant range Europe, SW Asia


  • 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 East-facing or West-facing

  • Exposure Exposed or Sheltered


  • Sand


  • Clay


  • Chalk


  • Loam


  • MoistureMoist but well-drained, Well-drained

  • SoilSand, Clay, Chalk, Loam

  • pHNeutral, Acid, Alkaline


  • 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 Prefers alkaline to neutral, moist but well-drained soil in full sun, but will tolerate acid soil and dry conditions. Survives well amongst short grass

Propagation Propagate by seed sown in autumn, or take softwood cuttings in late spring or early summer

Suggested planting locations and garden types Banks and Slopes Wildlife Gardens Wildflower meadow Gravel Garden Rock Garden

How to care

Pruning Pruning group 10 after flowering

Pests Generally pest free

Diseases Generally disease free

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