An investigation was undertaken to (1) determine maximum biomass production of fast-growing Salix clones on dry or nutrient-deficient land where adequate nutrients and water are supplied by irrigation and fertilization, (2) compare the efficiency of different irrigation-fertilization systems, (3) investigate the possibilities of successively increasing soil fertility by a fertilization routine adjusted to growth and uptake, (4) monitor the leakage of different nutrients to groundwater, and (5) make economic calculations with respect to the different irrigation–fertilization systems.