Effect of the application of blackcurrant seed post-extraction residues (BS) enriched via biosorption with Zn(II), Mn(II) and Cu(II) was examined in field tests on maize. As a nominal dose (100%), 2.5 kg of zinc, 1 kg of manganese and 0.5 kg of copper per hectare, were applied. The preparation was applied, also, in higher doses (150%, 200%). Crop yield and quality were assessed and multielemental analysis of grains was conducted. Grain yield obtained for maize treated with different doses of micronutrients (7.3 and 7.2 Mg ha(-1) for BS 100% and BS 200%, respectively) was higher than in control group (6.2 Mg ha(-1)) and similar to a commercial reference product (7.1 Mg ha(-1)). Bioavailability of micronutrients from BS was shown to be higher than from reference commercial fertilizer. The highest content of micronutrients delivered to plants was observed for groups fertilized with BS in nominal dose of micronutrients (1.79, 7.08 and 28.55 mg kg(-1) for Cu, Mn and Zn, respectively). The content of each micronutrient was 5.6% (Cu) 12.1% (Mn) and 12.6% (Zn) higher than in untreated group and 8.9% (Cu) 9.7% (Mn) and 8.7% (Zn) higher than commercial reference micronutrient fertilizer. New biocomponents are cheap and biodegradable carriers of nutrients which can be released in controlled way.