With the capabilities to measure redox potentials (EH) at a high temporal resolution, scientists have observed diurnal EH that occur in a distinct periodicity in soils and sediments. These patterns have been disregarded for a long time because minor fluctuations of the EH in the tens of mV range are difficult to interpret. Various explanations have been proposed for the origin of diel EH but a cohesive assessment of the temperature-dependency for field- and laboratory-based investigations is missing at present. In this study, we investigated spatiotemporal diel EH of previous long-term (up to 10 years) field- and lab-based monitoring data collected at high-temporal (every hour) and spatial (up to 6 depths) resolution. In addition, we set up a redox experiment where we manipulated the soil temperature (ST) by diel temperature cycles to assess the EH response. Diel fluctuations were absent for laboratory experiments with ΔEH of a few mV (daily EH-max - daily EH-min), but we found pronounced fluctuations up to ∼100 mV for field investigations. The spatiotemporal pattern in EH fluctuations was amplified in the topsoil during the summer months concomitant with ST. We showed for the first time that changes in ST during an incubation experiment altered the EH by -3.3 mV °C-1 and inferred that the diel EH were driven by the thermal conditions of the soil itself. This is particularly important when EH is measured close to the soil surface and underlines that minor fluctuations of the EH with a recurring periodicity should be carefully checked for its dependency with the soil and reference electrode temperature. Redox measurements should not be considered a routine determination and cautious handling of EH data by physical sound corrections is urgently needed in order to link ΔEH to daily biogeochemical cycling in soils.