Optimizing frequency and amount of irrigation needed to establish cool‐season turfgrasses

Abstract

AbstractLimited information is available on the optimal frequency and amounts of irrigation water needed to establish cool‐season turfgrasses from seed in arid environments. A 2 × 2 factorial study was conducted at New Mexico State University in 2012 and repeated in 2017 to investigate the effect of four irrigation treatments: two reference evapotranspiration (ETo) rates (60 and 120%), and two frequencies (daily and every other day [EOD]) on the establishment of several varieties of Kentucky bluegrass (Poa pratensis L.), perennial ryegrass (Lolium perenne L.), and tall fescue [Schedonorus arundinaceus (Schreb.) Dumort] (TF). Our hypothesis was that irrigation rates below 100% ETo replacement applied EOD would negatively affect turfgrass establishment. Turfgrasses were seeded in the fall and digital image analysis was used to estimate percent coverage. The Area Under the Curve model was used to estimate days after seeding needed to reach 50 (DAS50) and 90% coverage (DAS90). Statistical analysis indicated a significant interaction (p < .0001) between ETo and species and that irrigation frequency did affect establishment. Perennial ryegrass established the fastest and DAS90 was not affected by irrigation treatment. Kentucky bluegrass and TF established faster when irrigated daily at 120% ETo. Varieties within the same species all performed equally. In general, our study suggests that cool‐season turfgrasses can be established in arid regions using water conserving measures such as irrigating EOD at rates below 100% ETo replacement. Further studies are needed to determine lowest ETo replacement levels or irrigation frequency possible to achieve establishment.