Red-hot poker (Kniphofia 'Cobra')
Kniphofia 'Cobra' offers striking, torch-like summer blooms in tangerine fading to cream. This Red-hot poker is drought tolerant and low maintenance.
Complete Plant Information
Overview
The Kniphofia ‘Cobra’, commonly known as the Red-hot poker, provides dramatic vertical interest in the garden landscape. This outstanding herbaceous perennial is prized for its dense, bottlebrush-like flower spikes that command attention from early summer into fall. Gardeners appreciate the unique color progression of Kniphofia ‘Cobra’, featuring copper-orange blooms that gracefully fade to creamy yellow and finally white.
Established clumps of this Red-hot poker form a tidy basal rosette of linear, strap-shaped leaves, making it reliably attractive even when not flowering. Culturally, Kniphofia ‘Cobra’ thrives best in conditions simulating its native mountainous African habitat, prioritizing sharp drainage above rich moisture retention. Its robust nature, coupled with attractive form and color, secures its place as a staple in the perennial border.
Fast Facts
- Plant Family: Asphodelaceae
- Plant Type: Herbaceous perennial
- Hardiness Zones: USDA Zones 6-8
- Size at Maturity:
- Height: 2-3 ft
- Spread: 1.5-2 ft
- Bloom Time: June to July
- Bloom Description: Tangerine fading to cream
- Sun Exposure: Full sun
- Water Needs: Dry to medium
- Maintenance Level: Medium
How to Grow
Planting Kniphofia ‘Cobra’ should be done in humus-rich, well-drained soils. While it prefers evenly moist conditions during establishment, this Red-hot poker requires sharp soil drainage, especially heading into winter, as wet, heavy soils readily cause fatal root rot. Full sun exposure is ideal; however, tolerate light afternoon shade in extremely hot summer climates. Locate plants where they are somewhat protected from harsh winds if possible.
Maintenance is relatively straightforward. Promptly deadhead spent flower spikes to encourage prolonged bloom or tidy the appearance. In colder zones (5 and 6), crowns benefit significantly from winter protection; tie the foliage together in late fall to create a protective canopy that prevents freezing water accumulation. Applying winter root mulch also offers additional insulation.
As the new growing season begins, cut back the previous year’s foliage to about three inches above the ground. Established clumps of Kniphofia ‘Cobra’ generally dislike disturbance. If division is necessary due to overcrowding, attempt to sever offsets from the outer edges to minimize disruption to the main rhizomes. Note that named cultivars like ‘Cobra’ must be divided, as their specific color traits will not breed true from seed.
Landscape Uses
The upright, torch-like form of Kniphofia ‘Cobra’ makes it an outstanding vertical accent plant in any garden design. Its height (2 to 3 feet) allows it to command attention without overwhelming shorter border plants. Use them effectively as specimens planted singly to draw the eye, or install them in small groups for massed impact in a perennial border.
They pair wonderfully with plants that share similar sun and drainage needs, such as Sedums, ornamental grasses, or hardy Salvias. The bold structure of the Red-hot poker provides essential contrast against fine-textured or mounding perennials, offering architectural backbone throughout the summer months.
Standout Features
Flower Qualities
- Showy
Noteworthy Characteristics
Kniphofia is a genus known for its clump-forming, rhizomatous perennials featuring showy bottlebrush-like flower spikes, giving rise to common names like torch lily and red hot poker. The specific hybrid, Kniphofia ‘Cobra’, is valued for producing ornamentally impressive copper-orange flowers that transition beautifully to creamy yellow and white over their extended bloom period. Its foliage creates a dense basal clump, from which the naked flower scapes rise, typically reaching 3 1/2 feet tall.
Tolerances
- Rabbit
- Drought
- Dry Soil
Potential Problems
The Kniphofia genus is generally resistant to most serious insect and disease issues. The primary threat to your Red-hot poker is cultural: root rot, which occurs when the soil remains overly wet or poorly drained, particularly during winter dormancy. Ensure excellent drainage to prevent this failure mode.
In some regions, minor infestations of thrips may occasionally appear, potentially affecting the flower quality. If observed, management usually involves spot treatments or addressing environmental stress factors that make the plant more vulnerable.
Frequently Asked Questions
What hardiness zones is Kniphofia ‘Cobra’ suitable for?
The Kniphofia ‘Cobra’ is hardy in USDA Zones 6 through 8, requiring extra winter protection south of Zone 5.
How large does Red-hot poker grow?
This plant typically reaches a height between 2 and 3 feet with a spread ranging from 1.5 to 2 feet at maturity.
What sun exposure does Kniphofia ‘Cobra’ need?
This Red-hot poker demands full sun exposure for the best performance and strongest flower production throughout its blooming season.
When does Red-hot poker bloom?
Kniphofia ‘Cobra’ generally blooms from June to July, featuring its signature flowers that progress in color from tangerine fading to cream.
Conclusion
The unique, fiery spires of Kniphofia ‘Cobra’ provide unparalleled vertical drama and long-lasting summer color, making it a favorite perennial. Its adaptability to dry soil conditions after establishment offers a practical, medium-maintenance solution for sunny borders. Ensure sharp drainage is prioritized, and enjoy planning where this spectacular Red-hot poker will anchor next season’s garden design within its compatible hardiness zone.
Propagation Tips
While species plants of Kniphofia can often be successfully grown from seed, named hybrid cultivars like Kniphofia ‘Cobra’ must be propagated vegetatively. This ensures any new plants retain the exact characteristics of the parent, especially the distinctive bicolored bloom sequence that does not come true from seed.
The most reliable method for propagating established clumps is division. Wait until the plant is dormant or showing strong new spring growth, and carefully sever offsets from the edges of the main rhizome mass. Minimize root disturbance to the central crown when performing this division, as established clumps thrive when left undisturbed for many years.
Companion Planting
Due to the requirement for full sun and dry to medium water needs, Kniphofia ‘Cobra’ partners well with other drought-tolerant, Mediterranean-style plants. Consider pairing it with structural, sun-loving companions such as Lavender (Lavandula), Yarrow (Achillea), or Ornamental Grasses like Blue Fescue (Festuca glauca).
These companions share the necessary cultural needs, ensuring that overhead watering or fertilization intended for one plant does not negatively impact the Kniphofia. The fine texture of the grasses beautifully offsets the coarse, strap-like leaves and strong vertical spikes of the Red-hot poker.
