Canna 'Eden'

A spreading, herbaceous perennial with upright stems that grows up to 1m tall and wide.

Lemon yellow lily-like flowers produced throughout summer, contrasting with green lance-shaped foliage.

Prefers a sheltered site in full sun to partial shade with free-draining soil. Will tolerate drier soils.

Always choose healthy, well-grown plants and plant after autumn rains. Before planting, ensure the root ball is saturated and remove the planter pot with minimal root disturbance. Trim any broken roots and plant at the same level as in the container. Dig a hole twice the diameter of the root ball, press in and water once planted. Make sure plants are watered well until established if planting in a drier period. Plant with some general slow-release fertiliser and then every spring apply organic fertiliser (such as blood and bone) at a handful per square metre. Plant approximately 60cm apart.

If planting rhizomes in containers, fill a large pot 6 inches from the top with well-draining potting mix. Add perlite to help with drainage. If your pot is very large, you can plant two or three canna rhizomes in each pot. Backfill your pot or hole with additional soil until the rhizome and roots are well covered. Gently press the mix around the base and water in well.

Apply mulch annually to improve soil health and moisture retention and suppress weeds. Mulch also protects the rhizomes from the winter temperatures in colder areas. In a home garden, it is important that spent stems are removed at ground level as soon as the flowers finish. Stems that start to die back make the clump increasingly unattractive, so give them regular grooming to keep them looking good. The entire clump should be cut back to ground level in June or July when flowers finish. Lift and divide the entire plant every 3 to 5 years, as this helps maintain vigour.

Like all members of the ginger family, cannas are greedy growers. Give them plenty of fertiliser every spring and summer to ensure the clump remains vigorous.

In climates where the ground freezes in the winter, you can dig up your plants in autumn after the first frost, let them air dry for a few days and store the rhizomes in a cool dry place in a paper bag. You may get lucky and manage to preserve them for next spring planting.

Cannas in Auckland can suffer from rust in summer when there is high humidity. The affected stems should be cut back and burnt if possible. Rust spores are wind-borne, so if the material is left on the ground or composted it can re-infect the plants. They are also susceptible to fungal leaf spot. This is also best removed and burnt. Caterpillars, slugs, spider mites and earwigs can be troublesome, as they often chew flowers and foliage in summer.

Perennial Garden