Harvested bean plants should not be pulled out with the roots, but cut off close to the ground.
In this way, the roots and with them the nodule bacteria remain in the soil. They rot there and enrich the earth with humus and nitrogen. Besides, they do, that the vegetables planted in the country after beans show a particularly joyful growth, without nitrogen being given. Bacterial abundance, however, is only to be expected there, where lush beans have stood.