Earthworms are considered as natural aerators of soil because when they wiggle through the soil, they create air pockets in the soil by continuously feeding on soil along with plant clippings, compost, animal manure and excreting fine and smooth grinned excreta.
This fine excreta called castings that are biologically active natural fertilizers containing different types of bacteria with their metabolites like proteins and enzymes. In addition, the castings are rich in water-soluble micro and macro plant nutrients including nitrates, phosphorus, magnesium, potassium and calcium, manganese, copper, zinc, cobalt, borax, iron, carbon and nitrogen. Several studies have shown that the earthworm castings containing 5X of the nitrogen, 7X of the phosphorus, 3X of the exchangeable magnesium, 11X of the potash, and 1.5X of the calcium are immediately available in 6 inches of top soil for the plants to absorb.
