By Gardener Jack
When a gardener wants bold colour from a strong source that flowers intermittently throughout the year he could do much worse than employ cannas to fit the bill.
Cannas grows from rhizomes and in addition to flowers bears foliage that is similar to pointed heliconia leaves, giving a distinctly tropical effect. The flowers are large and are borne at the top of the plant, with new flowers appearing in quick succession. Canna blossoms may be yellow, orange or red, or combinations of these colours. What appear to be petals are really the stamens of the flower.
The height of cannas can vary considerably but standard species usually grow to about four feet. The plants have resting periods during the year but in the Bahamas tend to flower every season and the leaves are evergreen.
The complaint against cannas is that they often look very ragged. The flowers that are dying or have already expired tend to hang onto the plant, spoiling the effect of the bright new blossoms. The leaves are attacked by snails and slugs and have holes eaten into them. Frequent deadheading will solve the problem of the wilting flowers, and a regular application of snail bait should control the damage to the foliage.
Cannas occur naturally from the southern states of the USA through Central and South America to northern Argentina. They like full sun and rich well-drained soil.
Cannas are propagated by dividing their rhizomes, but a single plant will form a dense clump of plants in time. Cannas also propagate through seeds but the seeds are extremely hard and can often take months or years to germinate. If the seeds are scarified using a metal file and then soaked the process becomes quicker.
Variations occur when cannas are grown from seed. I planted orange seeds last fall and some of the resultant plants have beautiful yellow flowers.
Cannas planted en masse towards the edge of the property and normally seen at a distance are colourful additions to the landscape. I have also seen them planted along chain link fences where they provide ornamentation without obscuring the view.
Cannas and callas are often mentioned together even though they are not related. Callas - often miscalled calla lilies - have distinctly different foliage and the flowers are tubular. In Europe, callas are mostly called arum lilies and are used extensively for weddings. The Romans used callas for funerals and this tradition lives on. Callas are also a traditional Easter plant.
A calla flower is composed of a spathe and spadix. Although white is the predominant colour for the spathe there are now many colours to choose from, usually of a pastel hue.
Callas, like cannas, are grown from rhizomes and come to us from eastern and southern Africa. They are marshland plants and therefore need damp conditions to survive. Callas became naturalised in Western Australia and are now considered a pest. A beautiful pest, but a pest nevertheless.
In the Bahamas callas are best grown in containers and should receive plenty of light but not direct sunlight. I have seen them thrive on the borders of garden pools.