Fertilizers with potassium and nitrogen that dissolves in water can not be taken by the plants completely as they get washed with irrigation or rain water and enter into the under ground water. Only 20 -30 % of these fertilizers added to the soil can be taken by the plants. In order to solve this problem, slow-release fertilizers which dissolve slowly in the water have been developed. These fertilizers which are covered with polymers dissolves slowly when in contact with water and they reach the plant root. Thus most of the fertilizers enter the body of the plant. Such fertilizers are quite expensive and not widely used in our country.
As for the phosphorous fertilizers, they transform into a form which can not be taken by the plant after they dissolve or they are added to the soil and thus they are not taken sufficiently by the plants. When they are used in excessive amounts, they accumulate in the soil and they make the intake of the other nutrients difficult and decrease the fertility of the soil.
DELTA COMPOSED FERTILIZER types, which were developed to solve these problems, have the feature of improving the soil due to humic acid they contain. Their retention in soil is provided by forming a chemical link with nitrogen and potassium fertilizers and thus they do not get washed out of the soil with water. They can also convert the fertilizers into a form that can be received by the soil. It leads to a fertilizer saving at least 50%.
NPK fertilizers at various organic levels are produced in our plants upon demand. They improve the soil due to the humic acid which exists at various amounts in different types. They prevent the salt accumulation and aridity. As the nutrients enter the body of the plant, they are used in small amount but produce good yield. For example instead of 25 kg ammonium nitrate per decare use of 5 -10 kg Delta composed fertilizer is enough. There is no need for the use of animal- dung fertilizers.