A 3-year field study evaluated the effect of various rates of nitrogen fertilisers (0, 75, 150, 225 and 300 kg^.ha^-1 N) on total and true protein, as well as crude fiber contents in stinging nettle plants harvested at three development stages: before budding (the so-called ‘vegetative phase’), at full budding and full flowering. The results obtained show that increasing rates of nitrogen fertilisers increased the content and yield of protein, much higher in plants harvested at vegetative phase than over budding or flowering. Plant harvest at subsequent development stages increased the dry matter and crude fiber percentage in nettle plants but decreased that of protein. Leaves contained considerably more protein, however much less fibre than stems.

229-237