Canna edulis, or Achira, is native to the West Indies and South America. They are vigorous growers and will reach 10 ft (3+ m) in nature, but usually reach about 4-6 feet (1-2 m) in containers. The tubers are used as food in the Andean Mountains and it is the source of Arrowroot starch in Australia. They are hardy in USDA zones 7-12.
Blooming Time: In the greenhouse, they bloom all year long. The small 2½ inch (5 cm) long flowers are red with an orange to yellow lip. Although they are small, they are still quite showy.
Culture: Canna edulis need full sun to partial shade with a well-drained soil. In the greenhouse, we use a soil mix consisting of 1 part peat moss to 2 parts loam to 2 parts sand or perlite. The soil is kept moist at all times for optimum growth. Plants are fertilized on a weekly basis with a balanced fertilizer. They are very vigorous growers and will out grow most containers very quickly. Division of clumps in containers should be done on a yearly basis. As flowers fade, the stalks should be cut back to the ground.
Propagation: Canna edulis are propagated by division and by seed. The hard seed coat needs to be scarified and soaked in water for 24 hours. Seeds germinate in 14-21 days after sowing.
Canna edulis was featured as Plant of the Week January 10-17, 2003.
Guide to Past Plants-of-the-Week:
Cal's Plant of the Week was provided as a service by the University of Oklahoma Department of Microbiology & Plant Biology and specifically the late Cal Lemke, who used to be OU's botany greenhouse grower and an avid gardener at home as well. If the above links don't work, then try the overview site. You may also like to look at the thumbnail index. ©1998-2012 All rights reserved.