Kniphofia ensifolia

RHS Plant Profile

sword-shaped red-hot poker

Christopher Whitehouse

Herbaceous Perennial

A robust, evergreen perennial forming clumps of arching, narrow, blue-green leaves up to 1.5m long. The flowers open, base to top, pale yellow from reddish-orange buds in late summer to mid-autumn

Position

Full sun

Soil Types

Loam, Sand

Max Height

1-1.5 metres

Max Spread

0.5-1 metres

Size

Time to Maturity: 2–5 years
Max Spread: 0.5-1 metres
Max Height: 1-1.5 metres

Growing Conditions

Loam Sand

Moisture: Moist but well–drained
pH: Acid or Neutral

Position

Full sun

Aspect: South–facing or West–facing
Exposure: Exposed or Sheltered
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): H5

Colour & Scent

Season	Stem	Flower	Foliage	Fruit
Spring
Summer
Autumn
Winter

Botanical Details

Family: Asphodelaceae
Native to GB/Ireland: No
Foliage: Evergreen
Habit: Tufted
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
Name Status: Correct
Plant Range: South Africa

How to Grow

Cultivation

Grow in full sun and fertile, moist but well-drained soil that isn’t too wet over winter. See kniphofia cultivation for further advice

Propagation

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

Suggested planting locations and garden types

Coastal
Gravel garden
Cottage and informal garden
Flower borders and beds

Pruning

Cut down old flower stems after flowering; old or dead leaves can be tidied up or removed in mid-spring

Pests

May be susceptible to aphids, thrips, slugs and snails

Diseases

Generally disease-free