WaterCalcLabGarden Water Requirement Calculator
Apply an ET?/Kc water balance for a garden hydrozone. ET? is a daily input, not calculated weather data.
Your result
Bars compare only results in the same unit group. They are normalized, not a time-series forecast.
Planning result based on your inputs.
How this tool works
Apply an ET₀/Kc water balance for a garden hydrozone. ET₀ is a daily input, not calculated weather data.
Dnet = max(0, ET₀ × Kc × days − effective rain); Vgross = A × Dnet/ηExample calculation
The prefilled form is a worked example. Its base-unit inputs and expected outputs are shown below; use the reset button to restore it.
| Input | Example |
|---|---|
| Area | 100 |
| Reference evapotranspiration ET₀ per day | 4 |
| Crop coefficient Kc | 0.8 |
| Days | 21 |
| Effective rain for the period | 5 |
| System efficiency (separate losses) | 0.9 |
Frequently asked questions
How should I choose the inputs?
Use measurements and local records for the stated period. All preset values are illustrative examples, not recommendations.
What does this result leave out?
Simplified water balance, not a crop prescription. Supply local ET₀, a crop/stage-specific Kc and effective rainfall. It excludes capillary rise, soil storage changes, salinity and distribution non-uniformity.
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Method version 1.0 · Last reviewed: 2026-10-10