Abstract: An improved biological product which is effective in causing nitrogen enrichment soil is comprised of one of the following nitrogen fixing soil microorganism: azotobacter chroococum, actinomycetes thermophylus, a.o., mixobacter cytophagea, or myxobacter cellvibrio. The biological product also comprises a nutrient for the microorganism including a phytohormone such as B-indolylacetic acid, tryptophan, GA.sub.3, and Skatol. The nutrient material often includes a high molecular carbohydrate such as lactose or glucose and a nitrogenous source material such as urea, casein, albumin, or soy protein. Finally, the biological product includes an enzyme catalyst comprising wolfram or titanium, or a combination thereof. The enzyme catalyst probably reacts with the enzyme system of the microorganism in the conversion of the nitrogenous source material into nitrogen compounds which may be utilized as nutrient by plants.