About
Canna 'Roi Humbert' is a clump-forming perennial that typically reaches heights of 1.5 to 1.8 meters. It features wide, shiny leaves in a deep bronze hue, complemented by stems that have a purple tint. From mid-summer to mid-autumn, it produces vibrant red flowers that showcase an orange throat and distinctive markings.
About the genus
Canna are herbaceous perennials characterized by their rhizomatous growth and upright stems. They feature broad, oval leaves and prominent flowers that include petal-like staminodes along with smaller, colored petals and sepals. These blooms appear in clusters, such as racemes or panicles, during the summer and autumn months.
Growing conditions
- Sunlight
- Full sun
- Soil type
- Loam, Sand
- Soil pH
- Acid, Alkaline, Neutral
- Soil moisture
- Moist but well-drained
- Aspect
- South-facing, West-facing
- Exposure
- Sheltered
- UK hardiness
- H3
Plant details
- Plant type
- Conservatory Greenhouse, Herbaceous Perennial
- Habit
- Clump forming
- Foliage
- Deciduous
- Height
- 1.5-2.5 metres
- Spread
- 0.5-1 metres
- Time to full height
- 2-5 years
- Suggested uses
- Architectural, City and courtyard gardens, Coastal, Cottage and informal garden, Patio and container plants, Sub-tropical
Care notes
- Cultivation
- As a patio plant grow in pots of peat-free compost in a sheltered site in full sun. Plants can also be planted into a sunny border. Water freely and apply a high potassium feed every 2-3 weeks in the growing season. Lift the rhizomes in autumn when frost blackens the foliage. Store over winter in barely moist compost in frost-free conditions. See canna cultivation for further information
- Pruning
- No pruning required but deadhead to promote continued flowering
- Propagation
- Propagate by division of the rhizomes in spring
- Pest resistance
- May be susceptible to glasshouse red spider mite, aphids, slugs and snails
- Disease resistance
- May be susceptible to canna viruses