Cover crops can help recycle nutrients in organic farming with cereals. The study looked at how harvest time and straw management affect cover crop growth and nitrogen levels in the next crop. Red clover in the cover crop absorbed 40-77 kg of nitrogen per hectare. Residues from barley and cover crops could replace 61-85 kg of nitrogen fertilizer in the next crop. Leaving long straw stubble reduced nitrogen levels in cover crop shoots by 20%. Roots from barley and cover crops also provided nitrogen to the next crop. The availability of nitrogen from cover crop shoot breakdown varied between years and was affected by leftover straw from the previous crop.