Cotton Irrigation Scheduling: Which Method Is a Best Fit?

Irrigation management for cotton can become a difficult task due to the way cotton responds to irrigation and weather conditions. There are many irrigation scheduling tools available to producers, but determining which one may be the best fit for their operation can be a daunting decision. The main goal of this study was to evaluate different irrigation scheduling methods for cotton production in the southeastern US. A nine-treatment irrigation scheduling trial was implemented at the University of Georgia’s Stripling Irrigation Research Park. Cotton was planted during the middle of May and harvested during the middle of October. Watermark soil water tension probes integrated into a probe were installed in two of the three replications of each plot. The nine treatments that were implemented were a 45, 20, and 75 kPa soil water tension treatment, USDA-ARS Irrigator Pro, Crop Metrics Crop X, Valley Scheduling, Smart Irrigation Cotton App, the UGA Checkbook, and a rainfed treatment. A total of 21 inches of rainfall were received during the cotton production season. This can be considered a relatively wet season. This is also reflected in the low amount of irrigation which was applied via the UGA Checkbook (only 9.5 inches). Once the cotton is harvested and final yield calculated information such as irrigation water use efficiency (IWUE) can be calculated. This information can then be utilized by producers to determine which irrigation scheduling methods will be the best fit for their operations.