The effect of various rates of nitrogen fertilisers on macro- (N-NO₃, P, K, Mg, Ca) and microelement (Fe, Cu, Zn, Mn) contents in nettle plants harvested at three development stages was evaluated in 3-year field and laboratory study. The results obtained show an increase in nitrate and manganese contents in stinging nettle plants along with an increase in nitrogen fertiliser rate applied. Plant harvest at subsequent development stages (vegetative, budding and flowering) decreased the K, Ca, Mn and Cu contents. Plant harvest at full budding may be considered as the optimum one for P, Fe, Cu and Zn contents. Under the conditions of the experiment, the stinging nettle plant contents of K and Mn were too high, while the content of Ca – too low. Additionally the results of the analysis show a considerably higher content of minerals in leaves than in shoots.

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