The paper presents results of the studies carried out in 2002-2005, which aimed to assess the influence of intercrop fertilization on table potato yield and its structure under conditions of East-Central Poland. The following combinations of intercrop fertilization were applied: control object (without intercrop fertilization), farmyard manure, undersown crop (red clover, Italian ryegrass), stubble catch crop (oil radish, oil radish - mulch). The content of dry mass and macroelements (N, P, K, Ca and Mg) in biomass of intercrops was determined. In the first year after applying intercrop fertilization the potatoes were cultivated. During harvest a total yield and commercial yield of potato tubers were assessed, and after harvest a structure of tuber yield was evaluated. The results obtained in indicated that the highest amount of dry mass and macroelements was introduced into soil with Italian ryegrass and red clover respectively. The fertilizing value of red clover exceeded that of farmyard manure. No significant difference in fertilizing value was found between oil radish and farmyard manure. The plot fertilized with red clover was characterized by the highest proportions of table and seed potatoes, and the lowest participation of small tubers.
