Evapotranspiration: water lost by evaporation from soil + transpiration from plants. Reference ET (ETo) from weather data.

How to use for scheduling?

Crop ET = ETo × Kc (crop coefficient). Apply that depth via irrigation.

ET-Based Watering Calculator

Estimate watering needs based on Evapotranspiration (ET), crop factor, and irrigated area for efficient water use.

Estimate daily watering needs based on Evapotranspiration (ET), crop factor, and irrigated area.

Reference Evapotranspiration (ET0) (inches/day)

Crop Factor (Kc)

Irrigated Area (square feet)

Irrigation Efficiency (%)

The full supporting guide for this calculator is still being expanded. The tool remains accessible while we improve the educational content.

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