What formula is used to calculate plant water requirement?

• A. PWR = ETo + PF
• B. PWR = ETo x PF
• C. PWR = ETo - PF
• D. PWR = ETo / PF

Answer: (B)

The formula used to calculate plant water requirement is defined as the ET (evapotranspiration) adjusted by a particular plant factor (PF) that reflects the specific needs of the plants in question. In this context, PWR (Plant Water Requirement) is calculated as the reference evapotranspiration (ETo) multiplied by the plant factor (PF).

This means that the higher the ETo, which is a measure of water loss through evaporation and transpiration, the greater the water requirement for the plants, adjusted by the plant factor that takes into account the type of plants and their specific water needs.

By utilizing multiplication in this formula, it allows for a scalable approach to determining water needs based on both environmental conditions (as represented by ETo) and the characteristics of the plants being irrigated (represented by PF). This method is essential for improving water efficiency in landscaping and ensuring that plants receive adequate hydration without excess wastage.