An irrigation device comprising a moisture responsive barrier is provided. At least a portion of the barrier has perforations, at least some of the perforations are associated with a water swellable material. The perforations are configured to open as the water swellable material loses moisture and dries out and are configured to close as said water swellable material is exposed to and absorbs water, such as during a watering step. According to another aspect the irrigation method includes the steps of positioning a perforated barrier between a source of irrigation water and an area to be irrigated, wherein the perforations are associated with a water swellable material exposing the water swellable material to water to cause the water swellable material to swell to close the perforations and permitting the water swellable material to dry, to open the perforations, whereby the opening and closing of the perforations regulates the amount of irrigation water being applied across the barrier in the irrigation method.
