• 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

Santolina rosmarinifolia subsp. rosmarinifolia 'Primrose Gem'

lavender cotton 'Primrose Gem'

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
lavender cotton 'Primrose Gem'

© � RHS 2002

  • Other common names lavender cotton 'Primrose Gem'

  • Synonyms Santolina rosmarinifolius 'Primrose Gem'

  • Genus Santolina are aromatic, dwarf evergreen shrubs with entire or pinnately dissected leaves and dense, button-like flower-heads in summer

  • Family Asteraceae / Asteraceae

  • Details 'Primrose Gem' is a dwarf evergreen shrub with bright green, dissected leaves to 5cm in length, and clusters of long-stalked primrose-yellow flowers heads each 2cm in width

Characteristics

  • Foliage Evergreen

  • Habit Bushy

  • Fragrance Leaf

  • 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

    H5

Colour

Sunlight

  • Full Sun

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

  • Exposure Sheltered

Soil

  • Chalk

    Loam

  • Chalk

    Chalk

  • Chalk

    Sand

  • MoistureWell-drained, Moist but well-drained

  • SoilLoam, Chalk, Sand

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height

    0.1-0.5 metres

  • Ultimate spread

    0.5-1 metres

  • Time to ultimate height

    5-10 years

How to grow

Cultivation Easy to grow evergreen sub-shrub that thrives in hot, sunny, well-drained sites. Useful as a dwarf-hedging substitute although they can be short-lived

Propagation Propagate by semi-hardwood cuttings in late-summer

Suggested planting locations and garden types Drought Resistant Hedging & Screens Low Maintenance Flower borders and beds Ground Cover Gravel Garden Cottage & Informal Garden Patio & Container Plants Rock Garden

How to care

Pruning Pruning group 10. Trim back after flowering to maintain a dense, compact shrub

Pests Generally pest free

Diseases Generally disease free

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