• 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

Lycianthes rantonnetii

blue potato bush

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
blue potato bush

© RHS

  • Other common names blue potato bush

  • Synonyms Solanum rantonnetii

  • Family Solanaceae

  • Details L. rantonnetii is a lax, evergreen shrub producing clusters of lightly fragrant, purple-blue, funnel-shaped flowers in summer and autumn. These are followed by red berries

Characteristics

  • Foliage Evergreen

  • Habit Bushy

  • Fragrance Flower

  • Toxicity All parts can cause severe discomfort if eaten

  • 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)

    H3

Colour

Sunlight

  • Full Sun

  • Aspect South-facing or West-facing

  • Exposure Sheltered

Soil

  • Loam

    Loam

  • MoistureMoist but well-drained

  • SoilLoam

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 1.5-2.5 metres

  • Ultimate spread 1.5-2.5 metres

  • Time to ultimate height 2-5 years

How to grow

Cultivation May survive as a wall-shrub in very mild areas, or grow as a standard in a pot and take under cover for winter. Otherwise grow in a cool greenhouse or conservatory with shade from the brightest sun and moderate humidity. Plants will require support

Propagation Propagate by seed, or semi-ripe cuttings taken in summer or early autumn and rooted with gentle bottom heat

Suggested planting locations and garden types Wall-side Borders City & Courtyard Gardens Patio & Container Plants Mediterranean Climate Plants

How to care

Pruning Pruning group 9 if freestanding or pruning group 12 as a wall shrub

Pests Prone to aphids and glasshouse red spider mites whilst under glass

Diseases Prone to grey moulds under glass

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