Davao, 9 September 2009. Amaranth, commonly known as Chinese spinach, is a leafy vegetable found throughout the tropics and in many warm temperate regions. It is popular in India and other parts of Asia as the leaves provide two to three times the nutrients of other leafy vegetables.
Amaranths contain vitamins (A, B6, C, riboflavin, folate, and K) and dietary minerals (including calcium, iron, magnesium, phosphorus, potassium, zinc, and copper). However their moderately high content of oxalic acid inhibits the absorption of calcium and zinc, and also means that they should be avoided or eaten in moderation by people with kidney disorders, gout, or rheumatoid arthritis.
Although most Filipinos grow amaranth as a green leafy vegetable, it is planted in some parts of the world for its grain. The seeds are of “moderate importance” in the Himalaya region. It was one of the staple foodstuffs of the Incas. It was also used by the ancient Aztecs and other Native America peoples in Mexico.
Amaranth grains may be popped and eaten like popcorn (called alegrias in Mexico, laddoos in India and Pakistan), popped and ground into a delicious nutty-tasting flour, or ground without popping. Pancake-like chapatis made from amaranth flour is reportedly a staple in the Himalayan foothills.
Like the leaves, the seeds of amaranth are potent. Its protein content alone is higher than that of other world grains: amaranth, 16 percent; rice, 7-10 percent; and corn, 9-10 percent. Their combination of amino acids comes closer to a perfect protein (100) than any other major grains: amaranth’s 75-87; compared with corn (44), wheat (60), and soybean (68).
In addition, amaranth grain is high in lysine, a limiting amino acid in many proteins. A combination of amaranth and corn, for instance, scores an almost perfect 100.
Several studies have shown that like oats, amaranth seed or oil may be of benefit for those with hypertension and cardiovascular disease; regular consumption reduces blood pressure and cholesterol levels, while improving antioxidant status and some immune parameters.
Also, amaranth is an excellent feed for ducks. Agriculture editor Zac B. Sarian reported of a lady farmer from the Visayas who used kulitis, local name of amaranth to feed her 35,000 Cherry Valley ducks. “The kulitis is chopped and macerated mechanically and combined with kangkong, dampalit, okra, corn, copra and spirulina which she also grows,” Sarian wrote. She planted five hectares of her farm to kulitis, which was harvested daily. It was not unusual for her to collect 30,000 eggs a day.
Amaranth belongs to a small group of plants whose photosynthesis is exceptionally excellent. The sunlight they capture is utilized more effectively than in most plants and amaranths grow fast. Vigorous and tough, amaranths are self-reliant plants that require very little care. They germinate and grow well under adverse conditions.
As forage, very little is known about amaranth. Dr. D.H. Putnam of the Center for Alternative Plant and Animal Products of the University of Minnesota, reported that the leaves, stem and head of amaranth are high in protein (15-24% on a dry matter basis).
Amaranth was domesticated in Meso-America, along with corn, beans, and squash, over 6,000 years ago. At the time of the Spanish conquest of the Philippine islands, amaranth was one of the area’s principal food crops, with amaranth grains given as tribute totaling in the hundreds of thousands of bushels. Today, amaranth is a very important crop to rural farmers in Central and South America and to the hill tribes in Asia, New Guinea, and parts of Africa.
To grow amaranth in the backyard garden, Davao-based Mindanao Baptist Rural Life Center (MBRLC) Foundation, Inc. provides some pointers:
- Amaranth can be grown on any type of soil but for best results use a rich, loose clay loam soil with plenty of organic matter. Plenty of water gives the best growth.
- Before planting, ammonium sulfate is thoroughly mixed into the soil to a depth of 10 centimeters. Dried animal manure may be used if ammonium sulfate is not available.
- Amaranth is propagated by seeds. About 10 grams of seeds are needed to plant a square meter of bed. They are sown directly in a well-prepared raised bed at the rate of 30-50 seeds to every 100 centimeters of row. The rows are about 5 centimeters apart across the bed.
- When the plants are 7.5 to 10 centimeters high, they are thinned to 30 centimeters spacing.
- An improvised roofing over the plants can be built as a protection from heavy rains. This is kept on until the plants are about 5 centimeters tall. However, the plants can usually stand light rains.
- Frequent watering and weeding are necessary for good growth and yield. Mulching is recommended by placing rice straw or hulls on the surface after sowing.
- Harvesting may be started a month or so after planting. In some cases, the whole amaranth may be harvested by pulling it in bed. This is done if the plants are already 15 to 20 centimeters high. If the harvested leaves are to be sold, wash and bunch them in sizes according to their retail prices. The roots are usually left on to make bunching easier.
- When the plants reach about 25 centimeters in height, harvesting is done by cutting the plants close to the ground with the use of a sharp knife. When harvested in this manner, the crop can be ratooned to produce another crop, especially during the rainy season. Ratooning is advisable as long as the plants continue to give marketable green leaves.
- There are no serious insect or disease problems with this crop.