• 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 divaricata subsp. laphamii 'Chattahoochee'

wild sweet william 'Chattahoochee'

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
  • Other common names wild sweet william 'Chattahoochee'

  • Synonyms Phlox 'Chattahoochee'

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

  • Family Polemoniaceae / Polemoniaceae

  • Details 'Chattachoochee' is a low-growing semi-evergreen perennial to 15cm in height, with purplish stems, lance-shaped leaves and terminal clusters of slightly fragrant, purple-eyed lavender-blue flowers 2.5cm across

Characteristics

  • Foliage Semi-evergreen

  • Habit Mat forming

  • Fragrance Flower

  • 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

    H4

Colour

Sunlight

  • Partial Shade

  • Aspect East-facing or West-facing

  • Exposure Exposed or Sheltered

Soil

  • Chalk

    Sand

  • Chalk

    Loam

  • Chalk

    Chalk

  • Chalk

    Clay

  • MoistureMoist but well-drained

  • SoilSand, Loam, Chalk, Clay

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height

    Up to 10 cm

  • Ultimate spread

    0.1-0.5 metres

  • Time to ultimate height

    2-5 years

How to grow

Cultivation Grow in fertile, humus-rich, moist but well-drained soil in partial shade

Propagation Propagate by division in autumn or spring. Propagate by basal cuttings spring or propagate by root cuttings in early autumn or winter.

Suggested planting locations and garden types Underplanting of Roses and Shrubs Flower borders and beds

How to care

Pruning No pruning required

Pests May be attacked by phlox eelworm

Diseases May be affected by powdery mildews

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