Deficit irrigation of bermudagrass to conserve water while maintaining plant health: 2014–2015 summary.

The primary objective of this study was to begin to define irrigation requirements for a range of bermudagrass quality and color ratings during the warm season. The practice of irrigating below optimal conditions, called deficit irrigation, allows soil and turfgrass tissue to gradually dry during the summer. This study was conducted from June to Sept. 2014 and 2015 on twelve, 10.0- x 10.0-ft, well-established bermudagrass plots located at CPP. Three irrigation amounts (treatments) were arranged in a RCB design with four replications. Treatments were calculated so that the irrigation during the summer was 100%, 75% and 50% optimal (100%, 75%, and 50%). Results showed that turfgrass quality and color were significantly affected by irrigation treatment and date during 2014 and 2015. During both years, overall quality and color ratings were greater than 6.0 (acceptable) for the 100% and 75% treatments; the 50% treatment was not lower than 5.7. The ratings from 2015 would have been lower if the study was not terminated early because of 1.45 inches of precipitation on Sept. 15. Deficit irrigation is a viable water conservation tool. Results from this study indicate that 25% to 50% less irrigation than the optimal can be used during the summer while maintaining acceptable to minimally acceptable bermudagrass. At different locations, results from deficit irrigation would vary because of several factors, such as soil texture and climate.