Canna Black Knight

Canna ‘Black Knight’ is a bold, architectural perennial grown for its dramatic foliage and deep, richly coloured flowers. Large bronze to bluish-purple leaves form an upright, clump-forming plant, topped from mid-summer to autumn with striking, very dark red blooms up to 8 cm across. Its strong tropical presence makes it an excellent choice for borders and large containers.

Thriving in warm, sheltered positions, this vigorous Canna adds height, texture, and colour to sub-tropical and summer planting schemes.

Key Characteristics & Care

Flowers: Deep, dark red blooms up to 8 cm across
Foliage: Large bronze to bluish-purple leaves
Height: 1.5–2.5 m
Spread: 1–1.5 m
Growth Habit: Upright, clump-forming

Planting Time: Spring, after the risk of frost has passed
Position: Full sun
Aspect: South- or west-facing, sheltered site
Soil: Moist but well-drained soil; adaptable to loam or sandy soils
Soil pH: Acid, neutral, or alkaline

Watering: Water freely during dry periods
Feeding: Apply a balanced liquid feed monthly during the growing season

Hardiness: Tender. In colder regions, lift rhizomes in autumn once frost has blackened the foliage and store in barely moist compost in frost-free conditions. In mild, frost-free areas, rhizomes may be left in the ground with a deep, dry winter mulch.

Usage & Growing Tips

Uses: Ideal for tropical and sub-tropical borders, flower beds, large containers, and architectural planting
Maintenance: Deadhead spent flowers to prolong blooming; no pruning required
Propagation: Divide rhizomes in spring

Pests: May be susceptible to slugs, snails, aphids, and glasshouse red spider mite