857 Canavalia roseaCommon Names: beach bean, seaside bean, coastal jackbean, MacKenzie bean, bay bean Family: Fabaceae (bean Family)
Beach bean is a mostly herbaceous vine that trails along beach dunes and coastal strand. The thick, fleshy stem can grow to 20 ft (6.1 m) or more in length and more than 1 in (2.5 cm) in diameter. The stem is rather woody near the base and several branches radiate outward, forming mats of light green semi-succulent foliage. Beach bean has compound leaves with three thick, more or less rounded, fleshy leaflets, each about 2-3 in (5.1-7.6 cm) long. The leaflets fold up under the hot sun at midday. The flowers are typical pea flowers, purplish pink, about 2 in (5.1 cm) long and borne in erect spikes on long stalks. Beach bean blooms most of the summer and sporadically the rest of the year. The pods are flat and 4-6 in (10.2-15.2 cm) long. They are prominently ridged and woody when mature.
Beach bean has a pan-tropical distribution. It occurs naturally on seashores in the tropics and subtropics throughout the world. Beach bean grows on the upper beaches and sand dunes and on seaside cliffs. In the United States, beach bean occurs on the coasts of the central and southern Florida peninsula, southern California and southern Texas.
CultureThe sturdy, fast growing beach bean thrives in almost any well drained soil. It is highly salt tolerant. It will have to be pruned to be kept in check Light: Full sun. Moisture: Beach bean is drought tolerant. It tolerates watering as long as the soil has excellent drainage. Hardiness: USDA Zones 9 - 11. Propagation: Propagate beach bean from seeds. The seeds float and are distributed by ocean currents.
Beach bean hasn't really been discovered by the horticultural community yet, but we believe it has great potential for xeriscape gardening. It should be an excellent ground cover for dry sandy areas. Needless to say, it is a must-have for seaside gardens. Use beach bean as a ground cover where you have full sun, poor soil, and drought conditions. Beach bean is used as a biomass cover crop in Third World countries and in arid lands in Australia and Africa where its amazingly rapid growth quickly covers even the harshest soils. It is used to control soil erosion in many parts of the world. The young pods and seeds are edible and used for food in northern Australia. Mature seeds must be boiled or roasted to render them edible.
The genus Canavalia includes the tropical high climbing jackbeans, grown for food and forage in Africa and Southeast Asia. Beach bean became an important food for the British explorer, Captain James Cook and his crew during their voyage around the world from 1768 to 1771.
At least one nursery member of the Association of Florida Native Nurseries offers beach bean plants.
Mature seeds are toxic until they are cooked.
Steve Christman 10/14/00; updated 1/14/04