Soybeans are a major crop in countries including the U.S., Brazil, Argentina, India and China. It is also grown in some Canadian provinces and in smaller acreages in Asia and South Africa. And now Soybeans are being introduced as a crop in other parts of Africa.
While farmers harvest bean seeds, soybeans are grown for their oil and protein—those are the two end products. The oil is edible and has many industrial uses. The crude protein can be eaten by livestock and extracts of the protein can be consumed by humans. And in parts of the world, people need more high quality protein to supplement their carbohydrate-rich diet.
The ILSoyAdvisor is a place for growers and agronomists to learn more about growing soybeans and producing them profitably and sustainably. The information is practical, straightforward and readable. It is the only soybean management site of its kind available on the Internet. However, we have learned that readership is not limited to Illinois. We get viewers from around the globe asking about how to grow soybeans where there is no history or technical support. So they reach out to ILSoyAdvisor for some suggestions.
ILSoyAdvisor gets questions on growing soybeans in obscure places and while we are happy to dispense some general management advice, it’s always best to contact a local expert or another farmer who has experience growing soybeans and can tell you what to do and not to do. We can, however, provide a brief primer on the crop and its management.
Soya as a crop: Soybeans are a legume and oil seed crop that originates in China. It is a bushy plant that grows to a height of at least 3 feet or 1 meter and its growing season takes 90 to 120 days. And as a legume, if the seed is treated with a bacteria, it can fix much of its own nitrogen. It is a warm season crop, so it should be grown during the warmer part of the year and during the rainy season. Some countries experience distinct dry seasons and soybeans won’t perform well without irrigation.
Yield: Soybean yields are quite variable depending on variety, soil, weather and management. They can yield anywhere from 30 to 80 bushels per acre, which is roughly equivalent to 2000 to 6000 kg/ha. The higher yields require good varieties, good weather and exceptionally good management and investment. Smallholder yields at the start might range from 1 to 2 metric tons per hectare with very little investment or management.
Soil: Soybeans grow best in loose, well-drained soil that is rich in organic matter with a near neutral pH of 6 to 6.8. Soybeans aren’t tolerant of acid or heavy, wet soil. Agronomists say that soybeans don’t like wet feet, so well-drained soils are important.
Variety: The most important decision a farmer must make is finding a good variety to plant, that is, a variety with good agronomic characteristics that has good germination, clean seed and is adapted to where they farm. If you are planting soybeans for the first time, reach out to your national program or reputable seed dealer and ask for a variety that is adapted and performs. This is the most important decision you can make. There are more than 10,000 soybean cultivars available. Green-seed cultivars are tender and flavorable. Black-seed beans are used for drying. Yellow-seed beans are used to make soy milk and flour.
Planting and spacing: Plant seeds 1 to 2 inches deep (2.5 to 5 cm), 2 to 4 inches (5 to 10 cm) apart in rows 15 to 30 inches (40 to 75 cm) apart. Many farmers use commercial planters that precisely place the seed at the right depth and spacing and then cover the seed trench. You can also dig a seed trench and dribble the seed into the row, cover the furrow with soil and lightly firm the soil over the top. Don’t worry too much about over planting because soybeans will compensate by changing their individual structure if plants are too close together or too far apart.
Water: Seeds need water to germinate and emerge. Rainfall often is all that is needed to produce a crop. However if you experience a dry season, water the crop up and regularly water during flowering and pod formation. Avoid overhead watering because soybeans don’t like wet feet—it leads to root and stem rot.
Nutrients: Soybeans need nutrients like phosphorus and potassium. But generally they fix their own nitrogen. Adding animal manure, compost or some commercial fertilizer will improve yield. Generally growers have their soil tested for nutrient levels and then fertilize with phosphorus and potassium according to the soil tests and what is limiting. Soybeans—like any crop—yield better when key nutrients are available. If you already fertilize corn (maize) and wonder how to fertilize soybeans, follow the same practice as you do for corn but eliminate nitrogen.
Pests: A number of diseases and insects can attack soybeans. In developed countries growers scout their fields and apply pesticides to control pests. One good way to keep pests and diseases at bay is to rotate away for soybeans. If you are growing soybeans for the first time and very few soybeans are grown in your neighborhood, this crop is rarely bothered by pests or diseases. But keep the field clean of weeds and free of crop residue so that pests cannot harbor or survive to the next season. And always rotate to another crop.
Harvest: Green pod beans can be harvested when pods are green, full and plump or about half mature. Green seed for shelling and fresh use are ready for harvest 50 to 65 days after planting. Dry soybeans require 100 to 120 days to reach harvest. At this time the whole plant and pod will be brown or brownish yellow and seed moisture will be around 12 to 14 percent. Shell dry beans once the pods are fully dry.
Storage: Dry soybeans can be stored in a cool and dry place for months. However, fresh pods or whole seeds need to be eaten, marketed or stored in a refrigerator until used.
Click here for a production guide on growing soybeans in Northern Nigeria.
Click here to learn more about growing soybeans in Ghana.
Agronomist Daniel Davidson, Ph.D. posts blogs on agronomy-related topics. Feel free to contact him at email@example.com or ring him at 402-649-5919.