natural and organic fertilizer differs from chemicals in that they feed your plants while building the soil. Soils with lots of organic material remain loose and airy, hold more moisture and nutrients, foster growth of soil organisms, and promote healthier plant root development.if only chemicals are added the soil gradually loses its organic matter and microbiotic activity. As this material is used up, the soil structure deteriorates, becoming compact, lifeless and less able to hold water and nutrients. This results in increased amounts needed to feed plants.  n p k 20 5