• 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

Kniphofia thomsonii var. thomsonii 'Stern's Trip'

Thomson's red-hot poker 'Stern's Trip'

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
Thomson's red-hot poker 'Stern's Trip'

© RHS

  • Other common names Thomson's red-hot poker 'Stern's Trip'

  • Synonyms Kniphofia thomsonii var. snowdenii triploid variety
    Kniphofia thomsonii var. thomsonii triploid variety

  • Family Asphodelaceae

  • Genus Kniphofia may be evergreen or herbaceous perennials, with linear or strap-shaped leaves and erect stems bearing a dense raceme of tubular, usually pendent flowers

  • Details 'Stern's Trip' is a deciduous perennial with low-growing sparse foliage. The flowers are pale orange, opening from darker buds, widely-spaced on 1m tall stems, and produced from midsummer to mid-autumn

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

  • Partial Shade

  • Aspect South-facing or West-facing

  • Exposure Exposed or Sheltered

Soil

  • Sand

    Sand

  • Loam

    Loam

  • MoistureMoist but well-drained

  • SoilSand, Loam

  • pHAcid, Neutral, Alkaline

Size

  • Ultimate height 0.5-1 metres

  • Ultimate spread 0.5-1 metres

  • Time to ultimate height 2-5 years

How to grow

Cultivation Best grown in a sandy soil that has been enriched with humus, but any deep, moist but well-drained soil will do. Full sun is best; can tolerate partial shade but flowering is reduced

Propagation Propagate by division of established clumps in late spring. Propagate by taking offshoots from the crown

Suggested planting locations and garden types Flower borders and beds Coastal Cottage & Informal Garden

How to care

Pruning Old flower stems can be cut down after flowering

Pests Can be damaged by slugs and snails

Diseases Generally disease free

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