Most soy beans are grown in Tennessee, US. The plantation generally starts in between mid may and the beginning of July. Soybean also needs its share of heat. The suggested dates for plantation by the soybeans authority in Tennessee is April 25th to June 15. As many as 104 to 300 thousand seeds can be planted at once on a field as big as an acre, but it highly depends on the size of the seeds, the method of production and germination rate of the soybean. Soybean is best planted in rows which have been spaced out with almost 24 to 36 inches between each row. Cultivation should start two or three weeks after the plantation or when the plant reaches the height of 18 inches. This may take up to 5 week also.