• 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

Phlox douglasii 'Iceberg'

phlox 'Iceberg'

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
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  • Other common names phlox 'Iceberg'

  • Synonyms Phlox 'Iceberg'

  • Family Polemoniaceae

  • Genus Phlox may be evergreen or herbaceous, mat-forming or erect perennials or shrubs, with simple leaves and salver-shaped flowers in terminal clusters

  • Details 'Iceberg' is a mat-forming evergreen perennial with small awl-shaped leaves and blue-tinged white flowers 1.5cm in width, solitary or 2-3 in a cluster, in late spring and early summer

Characteristics

  • 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)

    H6

Colour

Sunlight

  • Partial Shade

  • Full Sun

  • Aspect South-facing or East-facing

  • Exposure Exposed

Soil

  • Sand

    Sand

  • Chalk

    Chalk

  • Loam

    Loam

  • MoistureWell-drained

  • SoilSand, Chalk, Loam

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height Up to 10 cm

  • Ultimate spread 0.1-0.5 metres

  • Time to ultimate height 5-10 years

How to grow

Cultivation Grow in well-drained, fertile soil in full sun or partial shade

Propagation Propagate by taking softwood cuttings of non-flowering stems in spring

Suggested planting locations and garden types Garden Edging Cottage & Informal Garden Gravel Garden Patio & Container Plants Rock Garden

How to care

Pruning Deadhead to prolong flowering

Pests Generally pest free

Diseases Susceptible to powdery mildews and a leaf spot

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