Small size of cabbage heads around 2.0 kg, preferred by the fresh market, may be attained by the choice of cultivar suitable for such purpose of production as well as culture practice, including reasonable rate of fertilization. The aim of the study was to evaluate the impact of increasing plant population combined with differentiated dose of nitrogen on yield of cabbage, its structure and plant composition. White head cabbage ‘Kalorama F₁’ cv. was planted in rows 45 cm apart and 50, 40, 35 or 30 cm within rows, which assured 44 000, 55 000, 63 000 and 74 000 plants per 1 ha, respectively. Nitrogen at the rates of 150 or 300 kg ha^-1 was used in 3 equal doses supplied as preplant and top dressing fertilization. Data obtained in the trial indicate that the dose of 150 kg N ha^-1 was a limiting factor for the increment of crop yield in higher than 44 000 plant population per 1 ha. In the case of application the dose of 300 kg N ha^-1 plants grown in population 63 000 and 74 000 per hectare produced significantly higher yield of heads if compared to the treatment with 44 000 plants. Taking into account the yield size and its structure it can be assumed that spacing 45 cm between plant rows and 40 cm distance in the row, which assure 55 000 plants per 1 ha is the optimum for production of cabbage heads weighted 1.0–2.0 kg, that meet the consumers expectation in the fresh market. Close plant spacing appeared to be beneficial for dry matter, vitamin C and total sugars contents and for decrease of nitrates accumulation. The enhancement of N dose to 300 kg N ha^-1 was beneficial for total yield of heads as well those weighted > 1.0 kg. The only change in plant composition under influence of heavy N fertilization was the increment of nitrates accumulation and decrease of Ca content in cabbage heads.

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