• 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

Lavatera trimestris

annual lavatera

annual lavatera

© RHS

  • Other common names annual lavatera
    common annual tree mallow

    royal mallow

    see more
  • Family Malvaceae

  • Genus Lavatera can be annuals, biennials, perennials or subshrubs, with long-stalked, palmately lobed leaves and large, funnel-shaped flowers in summer

  • Details L. trimestris is an upright annual, to 1.2m tall, with rounded, shallowly-lobed leaves and open funnel-shaped flowers to 10cm across. Many of the named cultivar selections are smaller in stature with a more compact habit. Flowers appear in mid to late summer in shades of pink or white, often with darker veining of the throat

Characteristics

  • Foliage Deciduous

  • 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)

    H4

Colour

Sunlight

  • Full Sun

  • Aspect South-facing or East-facing

  • Exposure Sheltered

Soil

  • Sand

    Sand

  • Loam

    Loam

  • MoistureWell-drained

  • SoilSand, Loam

  • pHNeutral, Acid, Alkaline

Size

  • Ultimate height 0.5-1 metres

  • Ultimate spread 0.1-0.5 metres

  • Time to ultimate height 1-2 years

How to grow

Cultivation Grow in light moderately fertile, well-drained soil in full sun

Propagation Propagate by seed sown in situ in mid-spring

Suggested planting locations and garden types Flower borders and beds City & Courtyard Gardens Coastal Cottage & Informal Garden Patio & Container Plants

How to care

Pruning Cut back after flowering

Pests Generally pest free

Diseases May be subject to stem rot, soil-borne fungal diseases and a rust

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