Canna Lily (Canna (family Cannaceae)) - How to Grow & Care Guide

Plant Snapshot

Common Name: Canna Lily
Latin Name: Canna (family Cannaceae)
Hardiness Zones: USDA zones 7–11 depending on cultivar and winter protection. Lift rhizomes below zone 7.
Typical Height: 2–6 ft (60–180 cm) depending on cultivar.
Typical Spread: 2–4 ft (60–120 cm) depending on clump and cultivar.
Bloom Period: Summer to fall, often from mid summer until frost in warm regions.
Soil Preferences: Rich fertile soil with consistent moisture and good drainage. Prefers neutral to slightly acidic pH around 6.0–7.5. Waterlogged or very dry soils reduce vigor and flowering.
Light Preferences: Full sun for best flowering. Tolerates light shade but flowers are reduced in heavy shade.
Toxicity: Not widely listed as highly toxic. Rhizomes of some species are edible. Ingestion may cause mild gastrointestinal upset in people or pets. Verify with local poison control for pet safety.
Propagation: Division of rhizomes in spring is primary method. Seed will produce plants but may not be true to parent cultivar.

Key Facts

Commonly called canna lilies though they are not true lilies.
Grown for large tropical foliage and showy upright flowers.
Overwinter as fleshy rhizomes that are lifted in cold climates.
Flowering typically runs from mid summer into fall where frost is absent.
Prefer full sun and consistently moist fertile soil.
Propagate mainly by dividing rhizomes in spring.
Available in a range of heights from compact garden types to tall architectural cultivars.

Canna Lilies are tender rhizomatous perennials valued for bold tropical foliage and upright, showy flowers. They perform best in full sun and consistently moist fertile soil and are commonly lifted as rhizomes where winters are frosty.

Identification

Commonly called canna lilies though not true lilies these plants belong to the family Cannaceae and feature large paddle shaped leaves and tall flower spikes. Height varies by cultivar from about 2 to 6 feet with spreads commonly 2 to 4 feet. Flower color and leaf pattern vary widely across garden varieties.

Best uses and where to grow

Cannas work as architectural focal points in mixed borders and tropical style beds where moist soil is available. Their upright form suits mass plantings and back of border positions. Full sun produces the best flowering while light shade will soften foliage color but tends to reduce bloom quantity.

Planting and timing

Plant or set rhizomes in spring after the last frost when soil is warming. Blooming generally runs from mid summer into fall where frost is absent. Many gardeners lift rhizomes for winter storage in climates colder than USDA zones 7 to 11 and replant in spring to renew growth and flowering.

Planting depth spacing and containers

Space plants to allow 2 to 4 feet between clumps depending on cultivar to prevent crowding and support airflow. Set rhizomes level with the soil or just below the surface so buds can sprout. Cannas adapt to large containers provided the potting mix stays fertile and consistently moist.

Soil light and watering

Choose rich fertile soil with steady moisture and good drainage and aim for a neutral to slightly acidic pH near 6.0 to 7.5. Full sun gives the best blooms. Poor drainage can cause rhizome rot while extended dry spells reduce flowering and produce smaller leaves and weaker stalks.

After flowering and overwintering

Remove spent flower stalks to tidy clumps and encourage continued growth. In regions colder than USDA zone 7 lift rhizomes and store them dry and frost free over winter. In warmer zones leave clumps in place where they can persist and increase year to year.

Controlling spread and maintenance

Cannas spread as clumping rhizomes and commonly form patches 2 to 4 feet across. Divide overcrowded clumps in spring to renew vigor and restore flowering. Crowded plants tend to produce fewer flowers so periodic division keeps beds productive and prevents accidental naturalizing in favorable climates.

Propagation

Division of rhizomes in spring is the primary and most reliable propagation method. Seed will produce plants but offspring often differ from named cultivars so seed grown plants do not reliably match the parent. Time divisions to give new shoots a full growing season to establish.

Frequently asked questions

How fast does Canna Lilies grow?: Growth rate depends on cultivar light and moisture. With full sun and regular moisture most varieties form a full clump and reach their mature height within a single growing season.
Are cannas hardy?: Hardiness varies by cultivar but many perform reliably in USDA zones 7 to 11. In colder areas lift rhizomes before hard frost for winter storage.
How should I overwinter cannas?: Lift rhizomes after foliage is killed by frost, clean and dry them then store in a cool frost free location until spring replanting.
Can I grow cannas in containers?: Yes large containers work well when you use fertile potting mix and keep the soil consistently moist while providing full sun for best flowering.
How do I propagate cannas?: Divide rhizomes in spring to make new plants. Seed is possible but named cultivars often do not come true from seed.