HighlightsAll tested smart irrigation technologies regulated irrigation based on real-time soil moisture and weather conditions.Treatments based on SMS, ET, or smartphone app applied less water than the comparison treatment by 51% to 63%, 28% to 66%, and 51% to 63%, respectively.The payback period for the different technologies ranged between 0 and 12 months.Abstract. A plot study comparing a variety of irrigation scheduling technologies was conducted in Gainesville, Florida, from 2015 to 2017. Our study objectives were to: (1) compare the ability of different irrigation scheduling technologies to bypass scheduled irrigation cycles and/or decrease water application; and (2) compare water savings. Twelve irrigation scheduling treatments were investigated, with each replicated three or four times. Treatments included time-based schedules without sensor feedback (WOS), with a rain sensor, deficit irrigation with a rain sensor, and non-irrigated. Also included were three soil moisture sensor (SMS) based treatments, three weather or ET-based treatments (ET), and two smartphone app-based treatments. Significant differences in turfgrass quality among all treatments (including non-irrigated) were not observed during the testing periods, which tended to be wetter than normal. Compared to WOS, the SMS, ET, and smartphone app treatments achieved water savings of 51% to 63%, 28% to 66%, and 51% to 63%, respectively, depending on treatment specifics. Inclusion of additional practices, such as a split irrigation strategy (half in the morning and half in the evening) and seasonal deficit irrigation, were shown to be advantageous in an area where rainfall is frequent and a substantial contributor to plant water needs. The SMS treatments saved water by bypassing scheduled irrigation cycles, the ET controllers saved water mainly through lower application depths, while the app-based treatments saved water through a combination of bypassing and applying lower irrigation depths. The payback period for the evaluated scheduling technologies ranged between 0 and 12 months. Financial and practical considerations should be included when recommending or acquiring one of these irrigation scheduling technologies. Keywords: Evapotranspiration controllers, Smart irrigation controllers, Smartphone apps, Soil moisture sensors.

Rain sensors (RSs) are devices that may help to irrigate residential landscapes more efficiently. When a predetermined amount of rain occurs, an RS interrupts the programmed irrigation cycle. When rainfall stops, RSs allow irrigation after a dry-out period. However, no actual RS dry-out times have been compared with soil dry-out times. The objectives of this study were (i) to determine the seasonal dry-out periods of two RSs; (ii) to estimate the dry-out periods of three soil textures (sand, loam, and clay loam) through a soil water balance model using numerical flow equations; (iii) to compare the dry-out period of these soil textures to the dry-out period of two RSs; and (iv) to propose recommendations for increased or decreased RS dry-out period, if any. Existing RS dry-out data from previous studies performed in Central Florida were assembled along with hourly weather data to estimate hourly turfgrass evapotranspiration (ET c ). Precipitation data were used with ET c to simulate soil dry-out, using the WAVE 3.0 model. Modeled soil dry-out times were compared against actual RS dry-out data. The average RS dry-out time was not different between the RS brands tested, which was around 19 h. The dry-out time of the sand-textured soil was different from the loam and clay loam, which were similar to one another. The dry-out times of the soils modeled were always above 52, 75, and 89 h for sand, clay loam, and loam, respectively. Therefore, these results show that the RSs tested do not follow the dry-out characteristics of any of the soil textures modeled. An electronic mechanism that could delay the RSs resuming to the allowing irrigation mode is recommended to the industry. Citation: Cardenas, B., and M.D. Dukes. 2018. Dry-out periods of rain sensors vs. soil dry-out: Water saving potential and recommendations. Vadose Zone J. 18:170185.

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The main objective of this study was to evaluate the long-term water conservation potential of two smart irrigation controllers when implemented in singlefamily homes with excess irrigation. Treatments were established in Orange County, Florida, across two types of soils and included homes monitored only (MO), homes that received an evapotranspiration (ET) controller or a soil moisture sensor (SMS) controller, and homes that received an ET or SMS plus an onsite specific programing and tutorial given to the homeowner (ETPgm or SMSPgm, respectively). All treatments resulted in significant water savings compared with the MO group, without negatively affecting the turf quality.Average irrigation reductions in sandy and flatwoods soils for ET were 21% and 17% and 26% and 31%, respectively, in the ETPgm group. The SMS group reduced irrigation by 18% and 42% in flatwoods and sandy soils, respectively, while the SMSPgm treatment applied 41% and 35% less water, respectively.

Year‐round irrigation water restrictions can be effective water demand management tools if people adhere to them. Awareness and understanding of these regulations have important implications for compliance and long‐term water supply goals. This study quantified irrigation restriction awareness‐knowledge and how‐to knowledge using survey data from residents with automated irrigation systems. Only half of those subject to irrigation restrictions were aware of these regulations; these irrigation restriction aware individuals reported varying perceived allowable watering frequency, implying that misunderstandings exist. Education, living in a homeowners association, hiring specific professionals, and information‐seeking preferences distinguished irrigation restriction aware from unaware individuals. Binary logistic regression revealed that when considered together, race, education, income, hiring a professional for fertilizer application, and living in a homeowner association significantly influence awareness‐knowledge. There are important opportunities to improve conservation outcomes by increasing both awareness and accuracy among target audience members.