In Poland, the content of available forms of elements is usually determined by the following methods:- phosphorus and potassium by the Egner-Riehm method (extraction with calcium lactate solution),- magnesium by the Schachtschabel method (extraction with calcium chloride solution),- microelements (zinc, copper, manganese, iron, molybdenum, boron) by the Rinkis method (extraction with hydrochloric acid solution). This means that in order to assess the soil content of the given elements, 3 separate analyses must be carried out, using different extractants and maintaining different extraction conditions. An alternative is therefore the possibility of using one analytical method - the Mehlich-III method - to assess the abundance of different macro- and micro-elements in the soil. Compared to standard methods, the Mehlich-III method 20% lower reagent costs, 40% lower labour costs 83% less water consumption, 95% less energy consumption. It also allows for more accurate determination of phosphorus fertiliser requirements.