Germination is epigeal with the cotyledons and stem emerging from the seedbed. Adequate rainfall is required from flowering to late pod fill in order to ensure good yield. Late plantings which result in flowering during the high temperature-low moisture period in July and August will reduce yield. High humidity and excess rainfall late in the season can result in disease problems and harvesting losses due to delayed maturity. Mungbeans are responsive to length of daylight so short days hasten flowering and long days delay it.
Varieties differ in their photoperiod response.
They do poorly on heavy clay soils with poor drainage. Performance is best on soils with a pH between 6.2 and 7.2 and plants can show severe iron chlorosis symptoms and certain micronutrient deficiencies on more alkaline soils. Mungbean has phosphorus, potassium, calcium, magnesium and sulfur requirements similar to other legumes which must be met by fertilizer additions if the soil is deficient in these elements. Seed is not generally treated with fungicides, insecticides or bactericides because of the possibility of ingestion of treated seed. Because the seed is small, careful handling and attention to planting machinery adjustments is necessary to ensure planting with little damage to the seed.