A recipe for the nutrient granular substrate for growing plants (the working name is "Zion") has been developed. The substrate contains all necessary for plant nutrient elements in the chemically bound state in high concentration; it does not contain any organic matter and nitrates, and does not need additional fertilization during the plant vegetation. All nitrogen in the substrate is contained in ammonium form. The substrate has been tested in the laboratory conditions in pot experiments for fertility and nitrates concentration in the biomass of the two cultures accumulating a large amount of nitrates that is leaf salad (Lactuca sativa L.) cultivar Afficion and ryegrass (Lolium perenne L.). The plants were grown on a 100 % substrate as well as on its mixtures (3-10 %) with different fruitless media - quartz sand, peat, and vermiculite. It appeared that in all the cases, when Zion has been used, the maximal content of nitrates in the plant biomass was 209 mg/kg dry, the minimal one was less than 50 mg/kg dry, which is lower by an order of magnitude than the admitted sanitary norm for the plants used in the study.