Legumes

Gardeners can feed their families and enrich the soil by growing legumes, such as green beans, soybeans, lentils, and peas. Legume roots produce their own nitrogen, which is a major fertilizer nutrient needed by all plants for growth. Nitrogen is produced in nodules that form on the roots of legumes, which contain Rhizobium bacteria. The bacteria take nitrogen from the air and convert it into a form the plants can use. When legumes are pulled up in the fall, excess nitrogen from the nodules is left in the soil. Excess organic nitrogen can be used by other plants the following growing season. It's considered organic nitrogen because it was produced naturally, making green beans or peas great rotational crops in an organic crop production system. Organic growers prefer organic nitrogen because of its natural origins and because it breaks down slowly in the soil, thus slowly feeding plants throughout the growing season. Synthetic nitrogen fertilizers tend to release nitrogen quickly and are harsher on the environment. Synthetic nitrogen fertilizers are generally applied in split applications during the season to mimic the slow release of organic nitrogen sources.