Climate changes lead to a rise in air temperature, which significantly increases the water needs of plants. Maintaining crop productivity will increasingly require the use of plant irrigation. The aim of this study was to assess the water needs of grapevines cultivated in the western provinces of Poland. The calculations were made on the basis of temperature and precipitation measurements collected at three meteorological stations in the period 1981–2010. Water needs were calculated as crop evapotranspiration, which was estimated by crop coefficients and reference evapotranspiration, determined using the Blaney–Criddle formula. The rainfall deficit was assessed by Ostromęcki’s method. The tendency to increase the water needs was observed in each subsequent decade of the thirty-year period, both in the whole growing season (May–October), as well as in June–August and July. The highest values of the linear correlation coefficient for the trend of time variability in water needs occurred from June to August. An analysis of water needs and rainfall deficits indicates the need for the additional irrigation of vineyards in western Poland, especially in very dry years and in June–August. Current research results are helpful in designing vineyard irrigation systems and allow an economical and efficient planning of grapevine irrigation.

The purpose of this research was to determine the water needs and results of drip irrigation of mid-early potato cultivar Courage. Studies were carried out in central Poland in 2011–2013 on very light soil. The experiment was designed as two-factorial trials with four replications. The first factor was drip irrigation: O = control (without irrigation), D = drip irrigation. The second factor was the nitrogen fertilization method: P = broadcasting, F = drip fertigation. Nitrogen fertilization was 120 kg N ha−1 on each plot. Crop coefficients for irrigation period were 0.4 in June and 0.6 in July and August. According to calculations based on the crop coefficients and correction coefficients acc. HargreavesDA model the water requirement of potato for June–August was 202 mm. Drip irrigation increased the marketable tuber yield by 55%. Irrigation water use efficiency increased from 257 kg ha−1 mm−1 in D + P to 264 kg ha−1 mm−1 in D + F. The productivity of 1 kg of nitrogen fertilization was 189 kg ha−1 in control non-irrigated plots and 321 kg ha−1 in drip-irrigated plots, and it rose up to 337 kg ha−1 when fertilization was applied by fertigation.

Climate warming increases the water needs of plants. The aim of this study was to estimate the water needs of grapevines in central Poland. Water needs were calculated using the crop coefficients method. Reference evapotranspiration was assessed by the Blaney–Criddle’s equation, modified for climate conditions in Poland. Crop coefficients were assumed according to the Doorenbos and Pruitt method. Water needs were calculated using the data from four meteorological stations. Rainfall deficit with the probability occurrence of normal years, medium dry years, and very dry years was determined by the Ostromęcki’s method. Water needs of grapevines during the average growing season were estimated at 438 mm. Upward time trend in the water needs both in the period of May–October and June–August was estimated. Temporal variability in the water needs was significant for all of the provinces. These changes were mainly impacted by a significant increasing tendency in mean air temperature and less by precipitation totals that did not show a clear changing tendency. Due to climate change, vineyards will require irrigation in the near future. The use of resource-efficient irrigation requires a precise estimate of the grapevines’ water needs. The study identified the water requirements for grapevines in central Poland.