Amaranth is a group of several dozen species of tall, leafy greens revered around the world for its nutritional content. Though several types of amaranth are regarded as weeds, many species are used extensively across the globe as greens, which are incorporated into soups, salads, stews, stir-fry and curries. The grain, known to have been cultivated as a food crop by early Meso-Americans, is also widely used and valued for its high protein content.
The genus Amaranthus is comprised of more than 70 species, many of which are used around the world as a highly nutritious food source. Thought to have originated in Mexico or Central America, amaranth now grows and is depended upon as a food source in Africa, tropical Asia and other subtropical regions. The plant withstands and even thrives in hot, dry conditions. The plant produces brightly colored seedheads ranging from creamy white to magenta. Each plant is capable of creating prodigious offspring, with a single plant producing more than 50,000 seeds in a single season.
The tiny seeds, and leaves, to a lesser extent, have extremely high protein content; seeds have between 12 percent and 17 percent protein by weight. Though high in oils, amaranth seed is low in saturated fat and high in fiber. It is a known source of the amino acid lysine, which is rarely available through plant food sources. Laboratory trials also indicate amaranth may contribute to lowered cholesterol levels, and other oils in the plant seed are necessary components in nervous system cell membranes.
Ancient Aztec Indians are known to have grown vast quantities of amaranth as a food crop as far back as 5,000 or 6,000 years. In addition to corn and beans, amaranth was an important crop presented to emperors, and the grain was used in connection with sacrificial and other ceremonial rites. Brought from the Americas to other parts of the world after the Spanish conquest, amaranth became a high-protein leaf vegetable crop in many parts of Africa and Asia, where it is still used as a herb in stews and soups.
With the advent of widespread corn and wheat production, amaranth all but disappeared as a food crop, though in recent years the ancient grain is being rediscovered for its exceptional nutritive qualities. Grain, flour and products such as pasta, bread, cereals and cookies are made using amaranth, and are increasingly available in health food or grocery stores.
One trait of amaranth species which makes it an excellent reproducer is its habit of dispersing seed via shattering seed pods, which cast ripe seeds in all directions from the parent plant. In gardens, this characteristic makes it undesirable, mainly because it creates an unsightly mess. Iowa State University has developed cultivars dubbed "Pillar Orange" and "Pillar Red," which retain the attractive height and colorful seedheads of other types of amaranth, but without the seed-scattering mess.
Pests and Diseases
There are few diseases which affect amaranth production or quality, but several insect pests may be problematic in larger stands of the grain. Infestations of tarnished plant bugs, flea beetles or the amaranth weevil can lead to extensive foliar damage or destruction of seedheads. Weevil larvae do the most damage by burrowing into the central stem of the amaranth plant, which causes rotting and plant stunting. Very little research has been conducted on widespread pest control in amaranth crop fields due to the very small acreage of amaranth production in the United States.