The aim of the present investigation was to assess the influence of rhizome mass on the success of plantation establishment and biomass yield of the bioenergy crop M. × giganteus during 10 years of cultivation. The experiment included three treatments with different rhizome masses: 10–20 g (very low); 25–35 g (low), and 40–60 g (medium mass). Planting density was 2 rhizomes m^-2. The plants were harvested by mowing of the whole above-ground biomass each year in February. Out of the total number of planted rhizomes, the lowest emergence was noticed in very low mass rhizomes. In the first season, the greatest number of stems and crop height were encountered under the treatment with the highest rhizome mass. In the second season, crop heights were almost equal in all treatments. During the first two seasons, the highest biomass yields were recorded under the treatments with the highest rhizome masses. Although the analyzed parameters were highest with the rhizomes of 40–60g during the crop establishing stage, starting from the third season of cultivation, high yields of above-ground biomass may be obtained also with lower mass rhizomes. Having the highest biomass yield (25.85±7.36 Mg DM ha^-1), the crop established with rhizomes of 25–35 g clearly stood out.