Irrigation Scheduling

Three methods dominate. (1) Soil-water balance accounting tracks the root-zone water budget daily: starting moisture + rainfall + irrigation − ETc = current moisture. Irrigation triggers when the deficit reaches a crop-specific depletion threshold, typically 40–60% of plant-available water. (2) Soil moisture sensors (tensiometers, TDR, capacitance probes) measure actual root-zone moisture directly at multiple depths. (3) Plant-based sensing (canopy temperature, stem water potential, thermal imagery) measures stress directly but is less common on commercial farms.

The FAO-56 method is the global reference. Daily ET₀ is computed from weather-station data using the Penman-Monteith equation; ETc = ET₀ × Kc with crop coefficients from FAO-56 tables (80+ crops). Effective rainfall is subtracted. The remaining deficit, divided by irrigation efficiency (drip ~90%, sprinkler ~75%, flood ~50%), gives the gross irrigation depth to apply. Typical irrigation intervals range from 1–3 days for drip on sandy soils to 7–14 days for sprinkler on clay loams.

Scheduling quality matters more than irrigation method. A well-scheduled sprinkler system often outperforms a poorly scheduled drip system because the wrong timing wastes water regardless of hardware. WiseYield's irrigation scheduler pulls daily weather, computes ETc per crop using FAO-56 coefficients, tracks cumulative deficit, and issues irrigation recommendations with target volumes — giving growers science-based scheduling without requiring a dedicated agronomist.