Fertigation in conjunction with traditional spread fertilization could improve the growth and yield of highbush blueberry. Study was conducted in the years 2002–2004 on a 10-year old plantation of highbush blueberry cv. ‘Bluecrop’. The effect of fertigation with 3 nutrient solutions (F-1, F-2, F-3) was investigated in comparison to drip irrigation (F-0) on growth and yield of highbush blueberry. Fertigation with nutrient solution F-1 containing (in mg·dm^-3): 100 (N-NH₄+N-NO₃), 30 P-PO₄, 60 K, 30 Mg, 0.30 B and 0.03 Mo, and from the water contents of 84.5 Ca, 47.9 S-SO₄, 4.8 Na, 6.6 Cl, 0.160 Fe, 0.054 Mn, 0.041 Zn and 0.009 Cu (pH 5.50, EC 1.10 mS∙cm^-1) had a positive effect (in comparison to the drip irrigation) on the fruit yield and single fruit mass of highbush blueberry cv. ‘Bluecrop’. An increase of nutrient contents in nutrient solution F-2 to the level of (in mg·dm^-3): 150 (N-NH₄+N-NO₃), 45 P-PO₄, 90 K, 45 Mg, 0.30 B and 0.03 Mo (the others as in F-1; pH 5.50 and EC 1.45 mS∙cm^-1) did not reduce the yield in relation to F-1, while it lowered the mass of one fruit. Yields of highbush blueberry under the influence of drip fertigation in relation to drip irrigation (F-0), at the optimal soil fertility obtained on the basis of spread fertilization, increased as follows: F-1 at 17.3%, F-2 at 21.9% and F-3 at 5.3%. The greatest effect of fertigation on yield of highbush blueberry was found in the year of soil drought, in which the highest rates of nutrient solutions F-1 and F-2 were applied. Fertigation with the nutrient solutions F-1 to F-3 increased dry matter contents of fruits, however it was lower than in drip irrigation. No nitrates or nitrites were detected in fruits of highbush blueberry. Highbush blueberry cv. ‘Bluecrop’ is a plant with high nutrient requirement. Average yearly nutrient rates for 10–13 years old plantation applied with the treatments F-1 and F-2 (sum of spread fertilization and fertigation) were: 19–24 g N, 10–12 g P, 7–10 g K, 9 g Ca, 6–8 g Mg and 4 g S·m^-2·bush^-1. For horticultural practice the nutrient solution F-1 could be recommended because of its advantageous effect on yield and the lowest fertilizer expenditure.

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