• 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

Verbena bonariensis

Argentinian vervain

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 Argentinian vervain
    purple top

    South American vervain
    tall verbena

    see more
  • Synonyms Verbena bonariensis 'Buenos Aires'
    Verbena brasiliensis misapplied

    Verbena patagonica

    see more
  • Family Verbenaceae

  • Genus Verbena can be annuals, perennials or sub-shrubs, with toothed or pinnately lobed leaves and small salver-shaped flowers in spikes, panicles or corymbs in summer or autumn

  • Details V. bonariensis is a tall perennial with erect, branching stems to 2m in height, bearing sparse, oblong leaves and large branched clusters of small, purple flowers from summer to autumn

  • Plant range South America

Characteristics

  • Foliage Deciduous

  • Habit Columnar/Upright

  • 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)

    H4

Colour

Sunlight

  • Full Sun

  • Aspect South-facing

  • Exposure Exposed

Soil

  • Chalk

    Clay

  • Chalk

    Loam

  • Chalk

    Chalk

  • Chalk

    Sand

  • MoistureMoist but well-drained, Well-drained

  • SoilClay, Loam, Chalk, Sand

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 1.5-2.5 metres

  • Ultimate spread 0.1-0.5 metres

  • Time to ultimate height 2-5 years

How to grow

Cultivation Grow in moist but well-drained or well-drained, moderately fertile soil in full sun. In cold areas, protect with a dry winter mulch

Propagation Propagate by seed in pots at 18-21°C in autumn to early spring or let it self-seed

Suggested planting locations and garden types Flower borders and beds Prairie Planting Gravel Garden

How to care

Pruning Cut down once flowering ceases

Pests Generally pest free

Diseases Generally disease free

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