What are the key factors that influence crop water needs in Variable Rate Irrigation?

Crop water needs in VRI are influenced by factors such as soil type, crop type, growth stage, weather conditions, and topography. For instance, crops in sandy soils require more frequent watering than those in clay soils. Similarly, crops in areas with high evapotranspiration rates, such as those in arid regions, require more water than those in cooler climates. Understanding these factors is crucial for adjusting water application rates in VRI.