A sprinkler system is controlled to ensure that a given geographic area receives sufficient watering without being over-watered. The sprinkler system, capable of being programmed to deliver a desired amount of water in accordance with a desired daily watering schedule, is programmed to deliver the desired amount of water every day unless interrupted. Rainfall information is received, and a signal is sent to interrupt the sprinkler system, causing the sprinkler system to: a) follow a predetermined watering schedule when there is no rain, in which case the sprinkler system delivers the desired amount of water following a predetermined number of days, n, without watering, or b) increase n by 1 or more days if the rainfall information indicates at least one significant rain event capable of providing the desired amount of water, and c) return to a) when n expires.
