Improving irrigation efficiency is essential for sustainable agricultural production. Smart irrigation technologies enhance water-use efficiency by integrating wireless communication, advanced sensors, and adaptive scheduling based on actual plant water requirements and weather conditions. Unlike traditional fixed-schedule timers, smart controllers dynamically adjust irrigation to optimize water use. This study aimed to compare three commercially available smart irrigation controllers: Hunter® Hydrawise (Hunter Industries, San Marcos, CA, USA), Orbit® B-hyve (Salt Lake City, UT, USA), and Rachio (Rachio Inc., Denver, CO, USA). The experiment was conducted at the Utah State University Greenville Experiment Station in Logan, Utah, USA. The experimental site (18.5 m x 6.4 m) comprised 12 plots (1.8 m x 1.8 m each), arranged in a completely randomized block design with three blocks, each containing four treatments (three smart controllers and one control). The control plot operated on a fixed timer: 20 minutes of irrigation daily managed by Rachio, whereas the other three smart controllers operated independently utilizing the weather data to schedule irrigation. Each plot was equipped with four sprinkler heads positioned at the corners. Controllers were installed and configured following manufacturer guidelines, utilizing Wi-Fi-enabled communication with their respective software applications. Each controller was configured, ensuring similar settings for a fair comparison, adhering to their respective technical features. Plugs of sage plants were transplanted in 7.5 L containers filled with Metro-Mix® 820 substrate. Initially, plants were irrigated daily for 20 minutes for two weeks to ensure proper establishment. Subsequently, the smart controllers managed irrigation based on real-time weather data, maintaining substrate moisture between 25-30% volumetric water content. Results showed significantly higher total water use in the control plots compared to those managed by smart controllers. Among the smart controllers, Hunter Hydrawise consumed significantly more water than Orbit and Rachio. Growth parameters including plant height, growth index, biomass, and visual appearance did not differ significantly across treatments. However, flower dry weight was significantly higher under Orbit compared to the control and Hydrawise, and similar to Rachio. Physiological parameters such as assimilation rate, stomatal conductance, maximum photochemical efficiency (Fv/Fm), Soil Plant Analysis Development (SPAD), Normalized Difference Vegetation Index (NDVI) remained consistent among all treatments. This study will be replicated during the upcoming summer to further validate the findings and enhance the reliability of the results.
