Canna (or Canna lily, although not a true lily) is a genus of approximately twenty species of flowering plants. The closest living relations to cannas are the other plant families of the order Zingiberales, that is the gingers, bananas, marantas, heliconias, strelitzias, etc.
The species have large, attractive foliage and horticulturists have turned it into a large-flowered, brash, bright and sometimes gaudy, garden plant. In addition, it is one of the world's richest starch sources, and is an agricultural plant.
Although a plant of the tropics, most cultivars have been developed in temperate climates and are easy to grow in most countries of the world as long as they can enjoy about 6 hours average sunlight during the summer.
The name Canna originates from the Celtic word for a cane or reed.
- Some species and many cultivars are widely grown in the garden in temperate and sub-tropical regions. Sometimes, they are also grown as potted plants. A large number of ornamental cultivars have been developed. They can be used in herbaceous borders, tropical plantings, and as a patio or decking plant.
- Internationally, cannas are one of the most popular garden plants and a large horticultural industry depends on the plant.
- The canna rhizome is rich in starch, and it has many uses in agriculture. All of the plant has commercial value, rhizomes for starch (consumption by humans and livestock), stems and foliage for animal fodder, young shoots as a vegetable and young seeds as an addition to tortillas.
- The seeds are used as beads in jewelry.
- The seeds are used as the mobile elements of the kayamb, a musical instrument from Réunion, as well as the hosho, a gourd rattle from Zimbabwe, where the seeds are known as "hota" seeds.
- In remoter regions of India, cannas are fermented to produce alcohol.
- The plant yields a fibre - from the stem - it is used as a jute substitute.
- A fibre obtained from the leaves is used for making paper. The leaves are harvested in late summer after the plant has flowered, they are scraped to remove the outer skin and are then soaked in water for 2 hours prior to cooking. The fibres are cooked for 24 hours with lye and then beaten in a blender. They make a light tan brown paper.
- A purple dye is obtained from the seed.
- Smoke from the burning leaves is said to be insecticidal.
- Cannas are used to extract many undesirable pollutants in a wetland environment as they have a high tolerance to contaminants.
- The leaves can be used to wrap tamales in a similar manner to banana leaves..
There is a very comprehensive list of corms and tubers here