Isolation from regular soybeans is not necessary. Because of the small seed size it is sometimes difficult to maintain accurate plant population. Natto soybeans usually have about 6000 seeds per pound so 200,000 seeds weight only about 33 pounds. Planting in early to mid-May is appropriate. Maintain at least medium P and K test levels.
Soybeans respond to residual fertility if soil pH level is monitored.
Lime should be applied to maintain a pH between 6 and 7. Lime increases yield by improving availability of some plant nutrients. Crop rotation and a good fertility program can help offset the insect problems. To achieve top quality soybeans, weed control must be accomplished early and continue throughout the growing season. Scouting for weed and grass infestations is necessary and especially important.