Arrowroot Canna indica

Arrowroot is a tropical and subtropical perennial plant that forms dense clumps and produces showy flame-red flowers on erect stems. The leaves are large, green to violet-green in color, and paddle-shaped. This species has been cultivated for over 4000 years as a food crop in Central and South America. The plant may grow to 8 feet tall and 3 feet wide. It is a member of the Cannaceae family.

Arrowroot is a native of Central America, South America, and the West Indies. Its primary habitats are sites with heavy rain-fall, disturbed areas, roadsides, and the outskirts of villages. The plant has been naturalized in the Southeastern United States, portions of Europe, sub-Saharan Africa, portions of Australia, and the Pacific Islands.

The genus name, Canna, is from the Greek word "Kanna," which means reed-like plant.

Arrowroot prefers sunlight, moist, well-drained soils with a preferably acidic pH. The plant may grow in soil types such as sand, clay, loam, and chalk. The rhizomes need to be spaced about 3 feet apart and 4- 6 inches deep after the last frost in the spring. The rhizomes will rot in poorly drained soils. Remove the spent flowers to encourage continuous flowering from August to October.  After the first frost in the fall, the plants should be cut to the ground. The plant is winter hardy in USDA Zones 8 through 11. In areas where the plant is not winter hardy, the rhizomes should be lifted from the ground for winter storage. The rhizomes should be stored in peat or vermiculite in a cool dry area. It is best to mist the rhizomes with water over the winter to prevent shriveling. Arrowroot may be propagated by division or by seeds.

The leaves may grow up to 24 inches long and 8 inches wide. They appear broad, waxy, and ovate to elliptical in shape. The large flowers appear at the top of the stalk. The corolla is about 2 inches long and at the lowest point, it is fused into a tube with the 3-4 free lobes. The blooms range in color from red to yellow-orange. The fruit is an ovoid capsule with soft spines. The small seeds are very hard and dark brown to black in color.

The rhizomes are edible and may be eaten raw. It is preferable to serve them cooked. The rhizomes are processed to produce a starch known as achira. It was a food source during the Great Chinese Famine of the 1950-1960s. The rhizomes may be used to produce vermicelli, white wine, and ethanol. The leaves have been used in South America to wrap tamales. The leaves also served as a food source for livestock. The seeds are used to make jewelry or musical instruments such as a rattle.

Hummingbirds, butterflies, bees, moths, and bats are attracted to the plant's flower. 

Arrowroot is a stunning and brilliant large plant for a cottage garden, informal garden, patio, or container. The flowers last about 1-2 days but new blooms appear constantly through the growing season.

Caution: Arrowroot has been declared invasive in South Africa, Australia, the Pacific Islands, Tanzania, and Ghana.

Diseases, Pests, and Other Problems:

Diseases affecting the Arrowroot include Canna rust, Canna yellow mottle virus, and Canna yellow streak virus. Some varieties are more disease-resistant. Pests commonly found include Canna leaf roller moth, Japanese Beetles, and Bird Cherry Oat Aphid

VIDEO Created by Elisabeth Meyer for "Edibles, Bulbs, and Houseplants" a plant identification course offered in partnership with Longwood Gardens.   

More information on Canna.