Forestry and Natural Resources
Clemson Extension Program Team
Forestry & Natural Resources
Publication Date
Summer 9-2-2025
Summary
Irrigation scheduling addresses two critical questions: when to irrigate and how much water to apply. Providing the optimal amount of water at the right time enhances water use efficiency, leading to improved crop production, while minimizing water losses and ensuring sustainable water management. This article compares two widely used soil water balance-based irrigation scheduling methods—Checkbook and FAO-56—by evaluating their principles, advantages, and limitations, with a focus on how each method tracks and manages soil moisture. To illustrate their differences, we present example calculations demonstrating how each method estimates irrigation timing and amount. The Checkbook method, widely adopted for its simplicity, offers a straightforward approach, while FAO-56 provides greater accuracy and efficiency, making it more suitable for long-term irrigation planning. By presenting both approaches, this article serves as a valuable resource for farmers, extension specialists, and irrigation managers, helping them choose a method that aligns with their needs and management goals.
Publisher
Land-Grant Press by Clemson Extension
Publisher City
Clemson, SC
Target Audiences
Extension water agents; stakeholders
Recommended Citation
Neupane, Adarsha and Samadi, Vidya, "Irrigation Scheduling Methods: Checkbook vs FAO-56". Clemson (SC): Clemson Cooperative Extension, Land-Grant Press by Clemson Extension; 2025. https://open.clemson.edu/forest_wildlife/61
