The study was carried out on a sandy soil. High bush blueberry (cv. ‘Patriot’) was tested during cultivation at different water regimes: W1 – soil moisture level at 50-60% of field water capacity (0.03 MPa) and W2 – soil moisture level at 90-95% of field water capacity (0,01 MPa), and at various NPK doses: 0 NPK – control, 1 NPK – 130 kg ha-1 (60 + 30 + 40), 2 NPK – 260 kg NPK ha-1 (120 + 60 +80) i 3 NPK – 390 kg NPK ha-1 (180 + 90 +120). The study showed a positive reaction of highbush blueberry to high amount of water in soil but not to large doses of NPK. The irrigated plants grew better, and developed more leaves and shoots. Positive changes in the anatomy and morphology of shoots and leaves were also observed. As an effect of good soil moisture conditions (90-95% of field water capacity) the yield of berries increased by 54%, but intensive mineral fertilisation did not increase the crop in the case of the Patriot cultivar.