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Tissue cultured banana plants were grown in a mix of river sand and CaCO3 and fertigated with acidic solutions salinized with NaCl. This was done to replicate the typical soil and fertigation condition of desert growers. Two different K sources (K2SO4 or KNO3) were used; either in "low concentration" fertigation solutions, or in higher (1.5-fold) concentrations. In each set of solutions, the nutrient concentrations, (excepting those for S), were identical when using K2SO4 or KNO3. The experiment was carried out twice, once in summer and once in winter. The aim was to assess differences in growth with time depending on the solution concentration and K source. Fertigation with the lesser concentrated solutions did not lead to a difference in growth between the K sources. Growth was enhanced during winter using the concentrated solutions, with the superiority of KNO3 as the K source not being clear. During summer, growth was depressed using the concentrated solutions when K2SO4 was the K-source, whereas it was enhanced when KNO3 was the K source. A number of additional parameters were measured in the winter trial: a greater number of leaves exhibited marginal necrosis when the more concentrated solutions were used, leaf number was slightly greater in the plants fertigated with the lesser concentrated mixes and differences in primary root number were not found. The study suggests high fertigation nutrient rates can be applied to banana plants grown in desert soils with positive effects regarding growth. However, if higher rates are applied, combinations of fertilizers rendering low EC's should be a prime consideration, with KNO3 being the preferential K-source in these conditions.