The cowpea (Vignaunguiculata) is an annual herbaceous legume from the genus Vigna. Due to its tolerance for sandy soil and low rainfall it is an important crop in the semi-arid regions across Africa and other countries. It requires very few inputs, as the plants root nodules are able to fix atmospheric nitrogen, making it a valuable crop for resource poor farmers and well-suited to intercropping with other crops. The whole plant is used as forage for animals, with its use as cattle feed likely responsible for its name.
Four subspecies of cowpea are recognized, of which three are cultivated. There is a high level of morphological diversity found within the species with large variations in the size, shape and structure of the plant. Cowpeas can be erect, semi erect (trailing) or climbing. The crop is mainly grown for its seeds, which are extremely high in protein, although the leaves and immature seed pods can also be consumed.
Cowpeas seeds provide a rich source of proteins and calories, as well as minerals and vitamins. This complements the mainly cereal diet in countries that grow cowpeas as a major food crop. A seed can consist of 25% protein and has very low fat content. Cowpea starch is digested more slowly than the starch from cereals, which is more beneficial to human health. The grain is a rich source of folic acid, an important vitamin that helps prevent neural tube defects in unborn babies.
The cowpea has often been referred to as “poor man’s meat” due to the high levels of protein found in the seeds and leaves. However, it does contain some anti-nutritional elements, notable phytic acid and protease inhibitors, which reduces the nutritional value of the crop. Although little research has been conducted on the nutritional value of the leaves and immature pods, what is available suggests that the leaves have a similar nutrition value to black nightshade and sweet potato leaves, while the green pods have less anti-nutritional factors than the dried seeds
Maize and cornmeal (ground dried maize) constitute a staple food in many regions of the world.
Maize meal is made into a thick porridge in many cultures
Maize is also used in making pap.
Maize meal is also used as a replacement for wheat flour, to make cornbread and other baked products.
Popcorn consists of kernels of certain varieties that explode when heated, forming fluffy pieces that are eaten as a snack.
Roasted dried maize ears with semi-hardened kernels.
Corn flakes are a common breakfast cereal in North America and the United Kingdom, and found in many other countries all over the world.
Maize is a major source of starch. Cornstarch (maize flour) is a major ingredient in home cooking and in many industrialized food products. Maize is also a major source of cooking oil (corn oil) and of maize gluten. Maize starch can be hydrolyzed and enzymatically treated to produce syrups, particularly high fructose corn syrup, a sweetener; and also fermented and distilled to produce grain alcohol. Grain alcohol from maize is traditionally the source of Bourbon whiskey. Maize is sometimes used as the starch source for beer.
Within the United States, the usage of maize for human consumption constitutes about 1/40th of the amount grown in the country.
Maize is also grown to feed livestock, as forage, silage (made by fermentation of chopped green cornstalks), or grain. Maize meal is also a significant ingredient of some commercial animal food products, such as dog food.
Most beans grow best in air temperatures of 70° to 80°F, and soil temperature should be at least 60°F. Soggy, cold soil will cause the seeds to rot. Beans need a sunny, well-drained area rich in organic matter. Lighten heavy soils with extra compost to help seedlings emerge.
Beans are self-pollinating, so you can grow cultivars side by side with little danger of cross-pollination. If you plan to save seed from your plants, though, separate cultivars by at least 50 feet.
Bean seeds usually show about 70 percent germination, and the seeds can remain viable for 3 years. Don’t soak or presprout seeds before sowing. If you plant in an area where beans haven’t grown before, help ensure that your bean crop will fix nitrogen in the soil by dusting the seeds with a bacterial inoculant powder for beans and peas (inoculants are available from garden centers and seed suppliers).
Plant most bush cultivars 3 to 6 inches apart in rows 2 to 2½ feet apart. They produce the bulk of their crop over a 2-week period. For a continuous harvest, stagger plantings at 2-week intervals until about 2 months before the first killing frost is expected.
Bush beans usually don’t need any support unless planted in a windy area. In that case, prop them up with brushy twigs or a strong cord around stakes set at the row ends or in each corner of the bed.
Pest And Diseases
Leaf miners are tiny yellowish fly larvae that tunnel inside leaves and damage stems below the soil. To reduce leaf miner problems, pick off and destroy affected leaves.
Striped cucumber beetles are ¼-inch-long yellowish orange bugs with black heads and three black stripes down their backs. These pests can spread bacterial blight and cucumber mosaic. Apply a thick layer of mulch to discourage them from laying their orange eggs in the soil near the plants. Cover plants with row covers to prevent beetles from feeding; hand pick adults from plants that aren’t covered. Plant later in the season to help avoid infestations of this pest.
Spider mites are tiny red or yellow creatures that generally live on the undersides of leaves; their feeding causes yellow stippling on leaf surfaces. Discourage spider mites with garlic or soap sprays. Using a strong blast of water from the hose will wash mites off plants, but avoid this method at blossom time or you may knock the blossoms off.
To minimize disease problems, buy disease-free seeds and disease-resistant cultivars, rotate bean crops every one or two years, and space plants far enough apart to provide airflow. Don’t harvest or cultivate beans when the foliage is wet, or you may spread disease spores. Here are some common diseases to watch for:
Anthracnose causes black, egg-shaped, sunken cankers on pods, stems, and seeds and black marks on leaf veins.
Bacterial blight starts with large, brown blotches on the leaves; the foliage may fall off and the plant will die.
Mosaic symptoms include yellow leaves and stunted growth. Control aphids and cucumber beetles, which spread the virus.
Rust causes reddish brown spots on leaves, stems, and pods.
Downy mildew causes fuzzy white patches on pods, especially of lima beans.
If disease strikes, destroy infested plants immediately, don’t touch other plants with unwashed hands or clippers, and don’t sow beans in that area again for 3 to 5 years
To dry beans, leave the pods on the plants until they are brown and the seeds rattle inside them.
Seeds should be so hard you can barely dent them with your teeth. If the pods have yellowed and a rainy spell is forecast, cut the plants off near the ground and hang them upside down indoors to dry.
Put the shelled beans in airtight, lidded containers.
Add a packet of dried milk to absorb moisture, and store the beans in a cool, dry place. They will keep for 10 to 12 months.