Soil nitrogen is the one of the primary nutrient plays a major role in achieving high crop yield. This paper mainly synthesizes importance of knowing percentage of nitrogen present in the soil, conventional laboratory testing methods, limitations of traditional techniques used and importance of nitrogen, rate of consumption during different stages of cultivation to achieve high yield, suitable soil for specific yield, potential. This paper also focused on the soil classification based on soil color approach, Machine learning algorithms, novel approaches used for nitrogen application to specific crop when consumption by the crop is more, the environmental effects due to excess use of nitrogen fertilizers and the research gaps., use of cutting edge technologies like augmented reality in future agriculture.