Soil fertility is an important factor to measure the quality of the soil as it indicates the extent to which it can support plant life. The fertility of soil is measured by the amount of macro and micronutrients, water, pH etc. Soil nutrients are depleted after every harvest and hence must be replenished. To maintain nutrient levels in the soil in case of deficiency, fertilizers are added to soil. Most of the farmers choose to approximate the amount of fertilizers and add them manually. However, addition of fertilizers in right amount is a matter of great importance as excess or insufficient addition can harm the plant life and reduce the yield. Use of modern trends and technology promises to provide a solution to the above problem. Though automated techniques for seeding, weeding, harvesting the crops etc. have been proposed and implemented, none of the techniques target at maintaining soil fertility. The proposed research aims at restoring the levels of Nitrogen, phosphorous, potassium in the soil by the measuring the amount of nutrients present. The presence of nutrients is determined by chemical processes and quantified using sensors. An automated system has been developed for the controlled addition of fertilizers in order to avoid excess/ deficient fertilizers in the soil.