Jane's Weather can provide insights on how much water is needed for your crop through our Evapotranspiration forecast. Set it up under alerts and notifications.
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From Agriculture Victoria:
Evapotranspiration provides a relatively objective and reliable estimate of the water requirements of actively growing plants in a farm situation. Evapotranspiration information can be used by irrigators to more accurately schedule irrigations to help achieve top yields and improve water productivity.
Evapotranspiration is an estimate of the loss of water from both plants and the soil. The main drivers of evapotranspiration are sunlight, wind, humidity and temperature.
‘Reference evapotranspiration’ (ETo) is commonly used as a standard estimate of evapotranspiration. ETo specifically refers to evapotranspiration from a reference stand of actively growing, well-watered grass, 120mm in height. For practical purposes, ETo provides a workable representation of the water requirements of good productive pasture on an irrigated farm.
ETo information enables irrigators to better match irrigations with the requirements of actively growing plants, thereby assisting to achieve higher yields and improve water productivity. ETo helps take the guess-work out of irrigating. A small, but regular improvement in irrigation scheduling can significantly increase over-all plant production and quality.
Business subscribers and Founding members can access this feature at Jane's Weather and have the insights for their locations of interest sent daily:
Essentially, this would indicate that 0.42L/ha of irrigation is required this week to keep the crop in optimal condition, if there was no rain falling.
You can read more about Evapotranspiration and how to use it for irrigation here at Agriculture Victoria.