Knowing the properties of water retention of different types of soils is an important step towards professional irrigation. The water retention properties can be determined with HYPROP device and abiding the gravimetric method in Richards pressure plate apparatus. The wilting point and field capacity are of great importance in the process of determing properties of water retention. The purpose of the study is to determine differences in the values of wilting points modeled with existing water retention curve models and measured with gravimetric method. 34 samples were taken in several apple orchards and vineyards in the valley of Vipava. Texture, procentages of silt, sand and clay and the content of water were determined for each soil sample. Water retention properties were measured with HYPROP device and its software HYPROP-FIT. The results showed that the most soil samples are of texture type silt loam and the least of clay loam, which indicate that the soils samples are from eutric brown soil region. In our research the van Genuchten model, in comparison with other used models and according to the root mean square error, was proven to be the most precise model in 14 cases. The results of differences in wilting point when using pre-existing models stretched from 1.5 – 28.4 vol. %. The differences in modeled wilting point and measured wilting point on the other hand from - 0.4 – 15.5 vol. %. To determine how much to irrigate, it is recommended to consider the measured wilting point, and not the modeled one, which is the result of pre-existing models.
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