Overview
Kniphofia northiae is a clump-forming, upright perennial in the genus Kniphofia, part of the Asphodelaceae family, with evergreen or deciduous; narrow, arching, strap-shaped or grassy foliage. It typically grows around 1.7 metres tall. Kniphofia northiae grows best in full sun, and tolerates fertile sandy or loamy soil soils and neutral to slightly acid pH. Its UK hardiness is rated H4–H6. Suggested uses include borders, architectural plant and cut flowers. It is native to South Africa.
About
Kniphofia northiae is a clump-forming, upright perennial in the Asphodelaceae, grown for its tall flower-bearing stems. It typically reaches about 1.7 metres and carries narrow, arching, strap-shaped or grassy leaves that may be evergreen or deciduous. Flowering runs from June to September. It is often used in borders, as an architectural specimen and for cut flowers.
Wikipedia contributors, CC BY-SA 4.0 — Kniphofia northiae
About the genus
Kniphofia is a genus of perennial flowering plants in the family Asphodelaceae, first described as a genus in 1794. All species of Kniphofia are native to Africa. Common names include tritoma, red hot poker, torch lily and poker plant.
Wikipedia contributors, "Kniphofia", CC BY-SA 4.0 — Kniphofia
In the garden
Native to South Africa, Kniphofia northiae makes a bold vertical statement with erect flower stems rising from a clump of narrow, strap-shaped foliage. Plants reach around 1.7 metres and produce their conspicuous blooms between June and September, making it one of the longer-flowering perennials for summer into early autumn. Position it in full sun on fertile sandy or loamy soil with a neutral to slightly acid pH; it favours conditions that remain moisture-retentive in summer but drain freely through winter. A south- or west-facing spot will help ripen flower stems, and the species tolerates either exposed or sheltered locations. In UK terms it sits in hardiness H4–H6 (average to very hardy) and is also suited to USDA zones 5–9, so it will survive most garden winters in milder and many cooler parts of the country provided winter drainage is good. Use Kniphofia northiae where vertical structure is needed: it works well towards the back of a mixed border, as a single architectural focal point or in a dedicated cutting patch. Expect long stems suitable for cutting and displaying when in bloom, and allow space for the clump to mature to its full height of about 1.7 metres.
Growing conditions
Best soil and position for Kniphofia
- Sunlight
- Full sun
- Soil type
- Fertile sandy or loamy soil
- Soil pH
- Neutral to slightly acid
- Soil moisture
- Moisture-retentive in summer, well drained in winter
- Aspect
- South or west facing
- Exposure
- Exposed or sheltered
- UK hardiness
- H4–H6
Plant details
Kniphofia northiae size, habit and characteristics
- Plant type
- Perennial
- Habit
- Clump-forming, upright
- Foliage
- Evergreen or deciduous; narrow, arching, strap-shaped or grassy
- Height
- 1.7 metres
- Suggested uses
- Borders, architectural plant, cut flowers
- Native to
- South Africa
Care notes
Pruning and caring for Kniphofia northiae
- Cultivation
- What most red hot pokers want is summer moisture combined with winter dryness. Plant on a free-draining site, water generously while the spikes are forming, then protect the crowns of less hardy kinds with a dry mulch or by tying the leaves up over the centre in autumn.
- Pruning
- Remove faded spikes at the base. Cut deciduous foliage down in late autumn; on evergreens pull away dead leaves by hand rather than shearing the whole clump.
- Propagation
- Divide established clumps in late spring — autumn division risks rotting. Species germinate readily from seed but take two to three years to flower.
- Pest resistance
- Usually undemanding, but aphids, thrips, slugs and snails can all take advantage of the crown and new growth.
- Disease resistance
- Healthy in suitable conditions. Crown and root rot follow winter waterlogging.
Frequently asked questions
How do I grow Kniphofia northiae?
What most red hot pokers want is summer moisture combined with winter dryness. Plant on a free-draining site, water generously while the spikes are forming, then protect the crowns of less hardy kinds with a dry mulch or by tying the leaves up over the centre in autumn.
Where is the best place to plant Kniphofia northiae?
Kniphofia northiae prefers full sun. It suits exposed or sheltered positions.
What soil does Kniphofia northiae need?
Kniphofia northiae grows best in fertile sandy or loamy soil soil. It prefers neutral to slightly acid soil. Aim for soil that stays moisture-retentive in summer to well drained in winter.
How do I prune Kniphofia northiae?
Remove faded spikes at the base. Cut deciduous foliage down in late autumn; on evergreens pull away dead leaves by hand rather than shearing the whole clump.
How big does Kniphofia northiae grow?
Kniphofia northiae reaches a height of 1.7 metres.
Is Kniphofia northiae hardy in the UK?
Kniphofia northiae has an RHS hardiness rating of H4, meaning it is hardy through an average UK winter, tolerating -10 to -5°C.
How do I propagate Kniphofia northiae?
Divide established clumps in late spring — autumn division risks rotting. Species germinate readily from seed but take two to three years to flower.
More in the Kniphofia genus
- Kniphofia 'Royal Standard'red-hot poker 'Royal Standard'
- Kniphofia gracilisRed Hot Poker
- Kniphofia rufaRed Hot Poker
- Kniphofia triangularisdwarf red-hot poker
- Kniphofia tuckii of gardensRed Hot Poker
- Kniphofia 'Ada'red-hot poker 'Ada'
- Kniphofia 'Erecta'red-hot poker 'Erecta'
- Kniphofia 'Goldelse'red-hot poker 'Goldelse'