Agriculture is by far the largest consumer of water worldwide, accounting for 70 percent of the total. Under the aspect of increasing global water scarcity, the need for a sustainable resource use is becoming ever greater. Soil moisture sensors in use today can help conserve water, but so far, they only measure how much moisture is present in the soil. However, the decisive factor for proper water management is how much water plant roots can draw from the soil. KIT researchers, together with TRUEBNER GmbH, have developed an electronic soil moisture sensor that can determine this measured variable. The sensor is based on a special porous ceramic disk from KIT, which is similarly absorbent to a root. Due to the electronic measuring unit added by TRUEBNER, the sensor can make a statement about the plant's suction tension and enables a sustainable use of the available water resources.