Abstract: A center pivot irrigation system with a controller for automatically starting and stopping the irrigation system based on the moisture level of the soil. A moisture level sensor is provided to detect the moisture level of the soil in the field at the predetermined location. When the moisture level falls below a predetermined level, a center pivot irrigation cycle is initiated. At least one complete irrigation cycle will be completed regardless of the status of the moisture sensor. Once started, the irrigation arm will continue irrigating until it reaches a preset stopping location. If, when reaching that location, the moisture sensor is still calling for additional irrigation of the field, a stop override will prevent the irrigation arm from stopping at the preset location and the irrigation arm will continue irrigating at least until it reaches the preset stopping location again.