A timer that facilitates a user's scheduling and controlling of the operation of an irrigation system for irrigating a property, the timer including a base unit electrically connected to the valve, and a handheld unit including a power source, a CPU, a valve controller, a memory device, and software stored in the memory device. The irrigation system includes a valve, a conduit, and a distribution unit that distributes fluid over an irrigation zone of the property. The handheld unit is used remotely from the base unit to modify an irrigation schedule of the valve. The irrigation schedule is used with the valve controller to operate the valve according to the irrigation schedule through communication with the base unit.