• 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

Phuopsis stylosa

Caucasian crosswort

  • Other common names Caucasian crosswort
    large-styled crosswort

  • Synonyms Crucianella stylosa

  • Family Rubiaceae

  • Genus Phuopsis is a mat-forming perennial with whorls of narrow, aromatic leaves and terminal clusters of small, narrowly funnel-shaped pink flowers

  • Details P. stylosa forms a wide mat of leafy stems to 20cm in height, with rose-pink flowers in summer

  • Plant range Caucasus, N. Iran


  • Foliage Semi-evergreen

  • Habit Mat forming

  • Fragrance Foliage

  • 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

  • Partial Shade

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

  • Exposure Exposed or Sheltered


  • Chalk


  • Loam


  • Sand


  • MoistureMoist but well-drained

  • SoilChalk, Loam, Sand

  • pHAcid, Alkaline, Neutral


  • 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 moderately fertile, gritty, moist but well-drained soil in full sun or partial shade. Suitable for use as ground cover on a bank, in the rock garden, or at the front of a border.

Propagation Propagate by seed or stem tip cuttings

Suggested planting locations and garden types Ground Cover Garden Edging Rock Garden Gravel Garden

How to care

Pruning Cut back after flowering to maintain compact habit

Pests Generally pest free

Diseases Generally disease free

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