The mung bean (Vigna radiata), often called the chickasaw pea in the U.S., grows up to 36 inches tall. It produces hairy black pods that are 4 inches long. Each pod contains tiny green, yellow, mottled black or brown beans, depending on the plant variety. High in magnesium, folic acid, phosphorus and thiamin, the beans are used in a wide variety of culinary dishes. The young, tender sprouts are also consumed.
The mung bean has been widely grown in India for centuries. It is also grown in parts of the US, South America, Australia, Africa and Asia as a food crop. A warm-season annual, the mung bean must be planted after all danger of frost has passed. In such states as Missouri and Oklahoma, the beans are planted commercially in June. The plants require at least 90 to 120 frost-free days to produce an ample crop, according to Purdue University.
The mung bean plant requires well-draining soil conditions. It will not tolerate a wet root system, which will cause disease to spread. High humidity can also cause the plant to suffer diseases. It prefers moist soil but not overly saturated. It does not tolerate drought well. If adequate rainfall or irrigation is not received, especially during the critical months of July and August, the plant will fail to produce an abundant crop.
Soil and Nutrients
The plant prefers to grow in sandy loam soil. It does not do well in clay-based soils. It does poorly in alkaline soil conditions and will quickly develop symptoms of severe iron chlorosis such as yellowing leaves. A soil pH of 6.2 and 7 is ideal for the plant to flourish. The mung bean belongs to the legume family and has the ability to fix nitrogen into the soil, but it requires additional nutrients to be added to its growth site to flourish, such as phosphorus, calcium, magnesium, potassium and sulfur.
Growth and Flowering
The mung bean grows in an upright bush habit, but some varieties also have a vining characteristic. Depending on the variety, the mung bean plant can be grown as a vine bean plant or a bush bean plant. During the early summer months, the mung bean plant produces an abundance of yellow flowers in clusters of up to 15 flowers at the end of each stem.
The plant continues to produce flowers throughout the early and mid-summer months. This means that the pod production is staggered with some pods maturing early for harvest and others being delayed. Harvest usually takes place when at least one-half of the pods have reached maturity. The pods can be harvested by hand or direct combining can be utilized in large fields.