Relating plant and soil water content to encourage smart watering in chestnut trees

•Is purposed an irrigation scheduling for chestnut trees, based on soil water content probe and soil water potential sensors.•The soil values are defined considering the optimal gas exchange and stem water potential previously found.•The optimal photosynthetic rate (9–11 μmolCO2m−2s−1) was reached when midday stem water potential were −1.2 to −0.5 MPa.•Irrigation based on capacitance probes should be such that guarantees soil’s water content is within 16% to 23%.•Irrigation based on soil matric potential, should be triggered every time sensors reads values above −100 cbar.