Quantifying the effects of water balance variables such as precipitation, evaporation and seepage on yield and vegetation dynamics in grassland is valuable and important, especially in view of increasingly extreme weather events. Grassland is one of the crops with the greatest water requirement. Every day, grassland needs around 2.5 l/m² of water to grow, which results in around 700 liters per kilo of dry matter. Based on the available long-term data series on soil water balance variables from lysimeters, year-to-year fluctuations and extreme values ​​can be analyzed and recommendations can be drawn up on water requirements, stock management and use in grassland. Such data is also important beyond the study area, as a basis for adaptation strategies to drought, and not just for agriculture.