• 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

Tropaeolum tricolor

three-coloured nasturtium

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
three-coloured nasturtium

© RHS

  • Other common names three-coloured nasturtium

  • Family Tropaeolaceae

  • Genus Tropaeolum can be annuals or perennials, bushy, trailing or climbing by twining stems, with simple or palmately lobed leaves and showy funnel-shaped flowers with five long-clawed petals and often a spur

  • Details T. tricolor is a summer-dormant, tuberous, perennial climber to about 1.5m with small, light green, five- or seven-lobed leaves. The small, yellow flowers are surrounded by a showy purple-tipped, orange-red calyx with a long red or purple spur, in all about 3cm long. Flowering takes place from winter to early summer

  • Plant range Chile

Characteristics

  • Foliage Deciduous

  • Habit Climbing

  • 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

  • Full Sun

  • Aspect South-facing or West-facing

  • Exposure Sheltered

Soil

  • Loam

    Loam

  • MoistureMoist but well-drained

  • SoilLoam

  • pHAcid, Neutral, Alkaline

Size

  • Ultimate height 1-1.5 metres

  • Ultimate spread 0.1-0.5 metres

  • Time to ultimate height 2-5 years

How to grow

Cultivation Grow under glass in good light with shade from hot sun. Plant tubers in a deep container of loam-based compost with added fine grit, starting into growth in autumn

Propagation Propagate by separating tubers when dormant in summer

Suggested planting locations and garden types Wall-side Borders Patio & Container Plants

How to care

Pruning No pruning needed - allow to die down naturally in midsummer

Pests No particular susceptibilities, but can suffer usual greenhouse pests such as glasshouse whitefly and glasshouse red spider mite

Diseases Normally disease free

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