Irrigation calculator

November 2014 | Prepared by Dr Ian Goodwin, DEPI Victoria | Future Orchards® irrigation tool

This Excel tool supports practical irrigation planning by helping growers convert weather and evapotranspiration information into an orchard water requirement. It is intended to complement field monitoring and local knowledge rather than replace them.

Growers can use the calculator to structure irrigation decisions around crop demand, irrigation-system performance and the amount of water already supplied. In practice, this makes it easier to compare planned irrigation with seasonal requirements and to identify periods where water application may need to be increased, reduced or redistributed.

The calculator is most useful when it is used alongside soil-moisture monitoring, knowledge of effective root depth and an understanding of the orchard block’s soil texture and water-holding capacity. It provides a repeatable way to turn irrigation planning into a measured process rather than relying only on fixed run times.