Leguminous plants (Fabaceae) are gaining more popularity both in Poland and in the World as people consume more beans with high-protein content – beans, peas, lentil, horse bean, soya, and white lupin. Beans of leguminous plants are a source of protein, iron, calcium, phosphorus, magnesium, iodine, potassium, easily soluble fibre, group B vitamins, antioxidants, and phytoestrogens.
Optimal content of basic nutrients in cultivation of leguminous plants should equal N – approx. 30, P-40-60, K-125-175, Mg-50-70, Ca-1000-2000 mg/l of soil. The yield of 20 t/ha of common bean absorbs approx. 80 kg of nitrogen, 30 kg of phosphorus, 60 kg of potassium, 8 kg of magnesium, and 56 kg of calcium from the soil.
It is necessary to mention that leguminous plants require nitrogen only in their initial development stage as they form root nodules with nitrogen-fixing bacteria in later stages. They also require seed treatment with symbiotic bacteria strains prior to sowing. Bi bean is recommended for these purposes.
It is worth mentioning that leguminous plants may leave soil with up to 200 kg of nitrogen for further crops.