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Evapotranspiration: A Complex Process with Magical Results

Evapotranspiration (ET) is the amount of water used (transpired) by a particular plant species combined with the amount of water lost (evaporated) from the surface of the soil under measured weather conditions. Evapotranspiration is generally expressed as the amount of rainfall needed to replace the amount of water transpired and evaporated over a given period of time, typically days or weeks. To complicate matters, each zone of your landscape has a different water requirement every day.

The process of collecting the data and calculating ET is even more complex than the word itself, one we spent years perfecting. We determine ET levels by analyzing local weather conditions (including solar radiation, temperature, wind and relative humidity) and calculating the amount of irrigation needed to replace the water lost by plants and soil due to these conditions. We utilize the Penman-Monteith equation, the worldwide standard for estimating plant water use established by the Food and Agriculture Organization (FAO) of the United Nations.

Why Does Evapotranspiration Matter to Me?

Our proprietary weather data is fed to HydroPoint controllers where our scheduling engine and depletion tracking model provides precise measurements of water needed by each plant as the weather changes. You’ll use the right amount of water at the right time, and not one drop more. We’re accurate to within 2% of what an on-site weather station would provide. Only HydroPoint uses weather calculated on so many dimensions and optimizes irrigation schedules accordingly. No one else in the industry comes close to providing the same data in the same timeframe. We reduce runoff, improve the health of your plants, lower your risk profile (think slip and fall) and fatten your wallet with savings.