The paper has two goals. The first one is to test the method proposed by Pietrzak in respect of the practical assessment of the geographical coverage of the agri-business sector, on the example of complex multiple-component fertilizers. The other goal was to verify the adequacy of the national level of analysis in that sector against the actual economic and spatial circumstances. The comprehensive analysis, which included the assessment of demand, supply and political as well as legal factors, carried out with the use of paired comparisons, weighting and point evaluation of individual factors, has shown that the relevant reference level in the analysis of complex multi-component fertilizers and decisions based on those analyses is the semi-global level, i.e. the supra-national regional level.