• 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

Lathyrus odoratus 'Heathcliff'

sweet pea 'Heathcliff'

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
sweet pea 'Heathcliff'

© RHS

  • Other common names sweet pea 'Heathcliff'

  • Family Papilionaceae

  • Genus Lathyrus can be annuals or herbaceous or evergreen perennials, mostly climbing, with pinnate leaves ending in a tendril, and showy pea-like flowers, fragrant in some species

  • Details 'Heathcliff' is a vigorous annual climber with greyish foliage and heavily fragrant, dark violet-blue flowers in summer and early autumn

Characteristics

  • Foliage Deciduous

  • Habit Climbing

  • Fragrance Flower

  • Toxicity Acute ingestion may cause mild stomach upset

  • 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 Exposed or Sheltered

Soil

  • Sand

    Sand

  • Clay

    Clay

  • Chalk

    Chalk

  • Loam

    Loam

  • MoistureWell-drained, Moist but well-drained

  • SoilSand, Clay, Chalk, Loam

  • pHAcid, Alkaline, Neutral

Size

  • Ultimate height 1.5-2.5 metres

  • Ultimate spread 0.1-0.5 metres

  • Time to ultimate height 1-2 years

How to grow

Cultivation Grow in a fertile, humus-rich, well-drained soil in full sun or partial shade. Incorporate organic matter into the soil before planting and feed with a balanced, liquid fertiliser once a month when in growth. Deadhead regularly to prolong flowering

Propagation Propagate by seed sown in-situ in mid-spring. Germination may be improved by pre-soaking or chipping before sowing

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

How to care

Pruning Remove after flowering

Pests May be attacked by aphids, slugs and snails

Diseases May be affected by powdery mildews

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