2019 ASHS Annual Conference

Landscape irrigation is important to maintain healthy and aesthetic plants in arid regions. Many urban landscapes are irrigated via automated systems programmed to customize application of the amount and frequency of water application. We conducted a survey in Arizona to determine current practices commercial landscapers use in managing and maintaining drip irrigation systems in landscapes and how to improve irrigation efficiency. Questions asked where the respondent was employed, the number and type of properties they maintained, and their responsibility related to drip irrigation. The survey asked questions about how irrigation schedules are developed, when they are changed, about the system hardware, and common system maintenance practices. We used 151 responses in the analysis. All respondents worked in commercial landscape businesses or municipal entities. Respondents maintained various types of properties including single-family residences, sports fields, roadsides, and golf courses. Almost 90% of respondents maintained sites with drip or micro-irrigation to water trees, shrubs and annuals. Respondents developed drip irrigation schedules based on experience and personal preferences, irrigation systems performance data, supervisor preference, or smart controllers. Infrastructure age and maintenance, and scheduling of irrigation systems can improve irrigation efficiency. Drip irrigation schedules were changed three to five times a year by 41% of respondents. Few respondents used controllers with soil moisture sensors. Landscapers know how to improve drip irrigation systems but often lack the funds and time to implement necessary changes. This survey and other inquiries found that landscapers did not have access to a user-friendly tool to schedule landscape drip irrigation. The University of Arizona Landscape Drip Irrigation Scheduler was developed to assist in making a schedule for drip irrigated landscapes (https://cals.arizona.edu/dripirrigation/home) to maintain healthy plants while saving water. The app uses historic evapotranspiration data and is accessible for zip codes in California, Arizona, and the greater Las Vegas area. Required input includes soil type, plant type (tree, shrub, cacti/succulent, ornamental grass, flower, or groundcover/vine), a relative water requirement for plants, and the number of emitters and their flow rate per plant. The resulting schedule for each irrigation zone shows the runtime and the dates each month when the zone needs to be irrigated. The schedule also displays the yearly total water use per zone and the yearly total water use of all zones. Comparing actual irrigation amounts of large commercial landscapes to the amounts recommended by the landscape drip app demonstrated significant opportunities for saving water by using the drip app.