The produced plants reduce the greenhouse effect because they fix CO₂ that contributes to the causing of the greenhouse effect with about 50%. The production of fertilizers is not only a costly process but it needs a considerable energy at the same time. Nowadays, the reduction of the proportion of the fertilizer is significant. One of the reasons of this is that during the production such by-products are produced in a big quantity in which the necessary vegetal nutrients can be found in a considerable measure these enrich the organic matter of soil. The latter is essential condition for the microorganisms in the soil, without which the sustainable plant cultivation can not be achieved. Besides high prices of artificial fertilizers the utilization of the wastes is economically justified. Finally the other reason for the reduction of a usage of artificial fertilizer is that the wrong use of the fertilizer may cause environmental pollutions. I examined the cultivation application of the sewage sludge in laboratory circumstances during my work.