Go wireless with automated irrigation control systems

If you are like 44% of nurseries in the U.S., you manually operate your irrigation, opening and closing valves by hand. This is a repetitive task that while not particularly arduous, likely requires stooping over repeatedly and is time consuming, as well as time sensitive.

Recent advancements in wireless communication led to the development of bluetooth (Bt) and long-range (LoRa) radio communication-based irrigation controllers, creating wireless solutions for large and small-scale nurseries. A team at the University of Tennessee recently partnered with a nursery to trial two Bt wireless controllers, the Hunter 4 Node and Baccara ii.ri, to each control a zone of Little Lime hydrangea (Hydrangea paniculata) in #1 containers. These were compared to manually controlling a zone. All zones were managed by the cooperating grower.

What did we learn? Both Bt systems were easy to set up, operate, and make programming changes. There were some challenges to using the rain delay and the sensor-based automation on the Hunter Bt controller. Plants grew larger and had more branches and blooms in the zones that were Bt-controlled compared with the manually controlled zone. The positive growth results in the two Bt zones are likely due to the container substrate being irrigated daily or twice daily compared to every few days in the manually controlled zone. Maximum and minimum water content were higher for the two Bt zones than the manually controlled zone.

Simultaneously, NC State University aided installation of two irrigation control systems at field nurseries; the Toro Tempus at Skip Warrick’s Scottree Nursery (Shelby, N.C.) and the Solem system at John McMakin Farms (Lyman, S.C.). Both growers applauded the national technical support provided by both system’s companies, as well as the onsite teams from their local agricultural irrigation suppliers, W.P. Law Inc. (Solem) (Greer, S.C.), and M.L. Irrigation (Toro) (Fountain Inn, S.C.). Each system relies on a one time purchase and installation of the long-range wide area network (LoRaWAN) gateway (i.e., no subscription fees like cellular systems) that sends and receives data from the installed irrigation components. Growers opened mobile apps on their phones and added new valves easily and intuitively to established zones. Latching solenoids remain closed until a command sent over the LoRaWAN signals a 9v battery to “latch” them open, then sends another signal after the irrigation event to close them. So there are no wires to provide a continuous 24v signal, or get struck by lightning, or tilled up or mowed. In fact, one grower simply is not using spools of copper wire he purchased to expand fields. He installed wireless controllers and is already planting. Moreover, an employee used to drive ¼ mile to distant fields to manually operate ball valves, then travel back to turn them off. Having digital access to newly installed flow meters allows him to distribute the total gallons per minute to irrigate more zones simultaneously from a distance. So not only are employee hours saved, but pump run times and overall irrigation volume is reduced. Not to mention, plants get watered when they need it rather than waiting on someone to drop what they are doing and drive over there.

To learn more visit nurseryleap.com and watch Skip Warrick of Scottree Nursery in Shelby, N.C., talk about the irrigation integration process himself at bit.ly/LEAPSkip, and send an email to leap4sustainability@gmail.com up to get invited to the monthly 30-minute series, LEAP Forward: Innovations in Nursery Automation to learn how other growers solve similar labor shortage challenges using automation.

Anthony V. LeBude and Anna Senter are with N.C. State University. Amy Fulcher, Karl McKim, Wesley C. Wright, Keegan Cole: University of Tennessee.

Labor, Efficiency, Automation, and Production: LEAP Nursery Crops Toward Sustainability is supported by the Specialty Crops Research Initiative Coordinated Agriculture Project award no. 2024-51181-43291 from the United States Department of Agriculture’s National Institute of Food and Agriculture.