CANNA: Canna Lily
Cannas often command oohs and ahhs in the perennial border. A bold tropical looking garden is not complete without the big leaves and voluptuous flowers of Cannas. Tall varieties offer a sensational backdrop for just about anything. Dwarf varieties can move into the middle or front layer of the border to offer good substance in the mix of plants.
Christopher Lloyd taught us to mix Cannas with finer, tall foliage such as Heilanthus angustifolia or ‘Lemon Queen’ and Verbena bonariensis for textural contrasts. Cannas also look great alone.
Every day I drive by a “hedge” of mixed cannas which provides seasonal privacy. This tropical privacy border is punctuated by Crinum and, yes, a perennial Brugmansia. I love to mix Cannas with other big bold foliage such as Kniphofia, Melianthus, Ricinus and Nicotiana sylvestris.
Cannas also teach us patience. They are one of the last perennials to emerge in the garden and in the nurseries. This is because Cannas require heat to wake up. They need at least 5 hours of direct sun per day, regular water and very good drainage.
These lush beauties also work well in containers. On my bike rides, I pass a parking strip with wine barrels filled with Cannas and other colorful annuals. If you plant tender Cannas such as ‘Intrigue’ or C. australis, you may want to pull the containers into the garage for winter protection. I have however, had these Cannas over winter in the ground if it was a mild winter or a protected sight.
Canna Journey's End
Cannas contribute big splashes of color to the garden with both their foliage and flowers. Canna ‘Tropicana’ (or Phasion) and ‘Pretoria’ both offer wonderfully colorful striped leaves. Wyoming and Futurity Red sport reliably perennial red foliage with orange or red flowers respectively. ‘Yellow King Humbert’ and ‘Journey’s End’ have flowers with spots and streaks. Dwarf varieties such s ‘Louis Cotton’ and ‘Lucifer’ reach about 2-3’ tall.
Ponds are another area in which to feature Cannas. They can tolerate 4-6” of water over the crown. It is essential to move pond cannas into a dry area for the winter. If your pond has afternoon shade you may want to try Canna ‘Stuttgart’ which has bold white streaked leaves.
Canna 'Tropical Rose'
You can purchase Canna rhizomes with spring bulbs or potted plants in late spring through summer. When planting bare rhizomes, amend the soil with compost and an all purpose granular fertilizer. Place the rhizomes in a 2-3” deep hole with the growing points facing up. Fill in the rest of the hole with a soil and compost mix.
Potted plants should be planted as any other perennials with special attention to soil drainage. To insure good drainage you may want to mix an inch of pumice and compost and starter fertilizer into the bottom of the hole. Loosen the roots and plant so that the soil line of the plant is even with the soil level of the ground. Water in with liquid seaweed to decrease transplant shock.
Whether you are creating a tropical back yard fantasy or planting some containers Cannas are sure to offer a bold and beautiful look.
Genus: Canna (Ka nuh)
Common name(s): Canna Lily, Indian Shot
Origin: Nine species native to tropical and subtropical New World.
Culture: Full sun (at least 5 hours of direct sun), fertile well drained soil, regular water. Cannas can grow around the edges of ponds as long as they are lifted in the fall to prevent rot over the winter. They can grow from 3’ (dwarf varieties) up to 10’ (Canna musifolia) tall and the clumps can creep indefinitely but slowly.
Pests & Diseases: Cannas are prone to rot in our soggy winter soils. They are also prone to the usual insects such as aphids and caterpillars. You can get foliage deformities or streaking if there are dramatic temperature changes while the leaves are unfurling. Often positioning cannas near a structure or large plant can help mitigate this situation. Leaf streaking can also be caused by a virus.
Maintenance: A relatively low maintenance group of plants if given good drainage. Give plants an all purpose fertilizer in spring as they are emerging. Flowers can be dead headed once the bloom has passed. Cut off the bloom head down to the next leaf.
A second bloom often emerges at this point. In fall cut canna stalks 1” above the ground after the leaves turn yellow. If they are planted in heavy soil, (or in zone 7 or lower), they should be dug in the fall to prevent rot or freezing out.
Dig up the entire root mass, leaving as much soil around the roots as possible. The soil should be moist, NOT wet. Let sit a few days if too wet. Put the whole clump inside a large plastic bag. Cover any bare roots or rhizomes with damp peat moss, filling the holes and gaps with the peat.
Fold the bag loosely closed and store in a cool place, but where the canna roots and rhizomes will not freeze. In the spring, you will notice the clumps start to sprout. If the weather is frost free, this is your sign to plant!
Propagation: Divide in late fall or early spring.