This new evapotranspiration application (ET1) allows the user to water their yard by using weather data to adjust the amount of water that needs to be used from day to day. This weather data is provided to the ET1 software by the use of weather applications developed specificity for ET1 software. Currently there are several weather applications and more on the way that will work with the ET1 application to retrieve weather data. Most of these weather data sources are free of any costs. In many cases the cost savings with our weather applications free data verses using a paid weather data service will pay for the ET1 software and hardware within a reasonable amount of time. Users have the option of using an on site tipping bucket rain gauge with the ET1 application. This will allow the user to use accurate on site rainfall. This system is targeted to property owners requiring up to 64 zones in their irrigation system.