• 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

Plectranthus thyrsoideus

flowering bush coleus

© Christopher Whitehouse
  • Other common names flowering bush coleus

  • Synonyms Solenostemon thyrsoideus

  • Family Lamiaceae

  • Genus Plectranthus can be annuals, evergreen perennials or shrubs, with opposite, ovate or heart-shaped, sometimes fleshy leaves, and 2-lipped, tubular flowers borne in whorls forming spikes or panicles

  • Details P. thyrsoideus is a bushy evergreen perennial with heart-shaped, round-toothed leaves to 10cm long, and spikes of bright blue flowers 1cm long, mostly in winter

  • Plant range Tropical E Africa

Characteristics

  • Foliage Evergreen

  • Habit Bushy

  • 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)

    H2

Colour

Sunlight

  • Partial Shade

  • Aspect South-facing

  • Exposure Sheltered

Soil

  • Sand

    Sand

  • Chalk

    Chalk

  • Loam

    Loam

  • MoistureMoist but well-drained, Well-drained

  • SoilSand, Chalk, Loam

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 0.5-1 metres

  • Ultimate spread 0.1-0.5 metres

  • Time to ultimate height 2-5 years

How to grow

Cultivation Grow under glass in areas prone to frost; may be grown outside in the summer. Use a John Innes No 2 compost and position in dappled shade. Apply a balanced liquid fertiliser once a month and water freely. In winter much less water is required

Propagation Propagate by seed in temperatures of 19-24°C (66-75°F) when they are ripe. Can also be propagated by softwood cuttings any time of year

Suggested planting locations and garden types Patio & Container Plants

How to care

Pruning Pinch out tips of young plants to encourage bushy growth

Pests Generally trouble free

Diseases Generally trouble free

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