Tensiometer-based irrigation scheduling with different fertilization methods in blackcurrant cultivation

Drip irrigation has been successfully introduced in blackcurrant production, but further knowledge of irrigation scheduling and fertilization is needed. For this study, three different drip irrigation thresholds, at - 150 hPa, - 300 hPa and - 600 hPa, in combination with either fertilizer in fertigation or broadcast were applied in a trial carried out in 2001 - 2003 in southwest Finland. Only a few significant differences were observed in the effects of various treatments on flowering, yield, size of berries or vegetative growth of blackcurrant ( cv. 'Mortti'). The soluble solids content ( Brix) was highest when using fertigation and irrigation threshold of - 150 hPa. Based on this study and earlier studies, the optimal soil moisture measured with tensiometer in sandy soils is at least - 270 hPa or even more moist. The soil moisture effect depends on soil nutrient status.