The subject of studies was to evaluate the influence of hop fertilization with potassium salt and potassium sulfate in autumn and spring on the yield and chosen qualitative elements of cones. Fertilizers were applied in the same objects for three following years (133 kg K·ha⁻¹) and evaluated on a background of control object (with no potassium fertilizer). Significantly higher cone yields (by 11.7%) were achieved on the objects with potassium sulfate than with potassium salt for the 3-year period, on average. However, in following years, the differences between objects with KCl and K₂SO₄ became lesser, what suggests alternating fertilizers application or dividing the whole dose onto autumn (in form of KCl) and spring one (in form of K₂SO₄). For both fertilizers, the autumn date of application appeared to be better although differences achieved were slight and statistically insignificant. Results of mechanical analysis of the cones confirmed positive effect of both fertilizers, especially potassium sulfate in relation to control object. Dates of fertilizer application did not show clear effects on particular elements of cone’s mechanical analysis.