Smart irrigation control systems typically include either a stand-alone controller
or an add-on device that interfaces with a conventional clock-type controller. The
weather or soil moisture-based technologies incorporated into these devices allow
them to function similar to a thermostat. Like a thermostat, the devices permit
irrigation to occur when needed rather than on a preset schedule. Regardless of
the specific method or technology, the concept is for the appropriate irrigation
quantity to be applied at the appropriate time