About

Canna 'Ra' is a substantial perennial ideal for aquatic and bog settings, reaching heights of over 1.8 meters and forming a broad clump. It features slender, grey-green foliage and produces large lemon-yellow blooms on tall stems from midsummer through autumn.

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

Soil pH

Acid, Alkaline, Neutral

Soil moisture

Poorly-drained, Moist but well-drained

Aspect

West-facing, South-facing

Exposure

Sheltered

UK hardiness

H3

Plant details

Plant type

Conservatory Greenhouse, Bogs, Herbaceous Perennial, Aquatic

Habit

Clump forming

Foliage

Deciduous

Height

1.5-2.5 metres

Spread

0.5-1 metres

Time to full height

1-2 years

Suggested uses

Architectural, Patio and container plants, City and courtyard gardens, Coastal, Cottage and informal garden, Sub-tropical

Care notes

Cultivation

In summer, water cannas (often bred from Canna glauca) can be placed in containers in ponds with no more than 15cm (6in) of water over the roots. They are also suitable for well-watered borders or conservatories where potted plants can be stood in deep saucers of water. Before autumn frosts, bring plants from outdoors into a frost-free greenhouse or conservatory. Keep the pots moist but not saturated. In April, increase temperatures and plant the sprouted plants out in late May when the risk of frost has passed

Pruning

Deadhead regularly to promote flowering, allow to die back naturally in autumn

Propagation

Propagate by division of rhizomes in spring

Pest resistance

May be susceptible to glasshouse red spider mite, aphids, slugs and caterpillars

Disease resistance

May be susceptible to canna viruses