On-farm Evaluation of Mesh Wireless Network for Monitoring Moisture of Containerized Ornamental Crops

As the availability of water decreases and the cost of water and energy increases, ornamental nursery producers are becoming uncertain of water security, increasing concern about changing regulatory pressure and the potential impact these factors may have on their budgets.  This has resulted in nursery professionals exploring new methods to improve irrigation efficiency.  Container production systems pose many challenges including variation in species and plant architecture, container size, soilless substrate composition and cultural management practices (use of plant growth regulators, pruning). Furthermore, containerized crops require intensive irrigation management with a small water buffering capacity when compared to field crops grown in soil. With the assistance of PureSense Environmental Inc., mesh wireless networks equipped with remote substrate moisture sensing technology were deployed in 2010 and 2011 at two Oregon nurseries, Woodburn Nursery and Azaleas Inc. and Bailey Nurseries, Inc., to evaluate its potential to improve irrigation management decisions in ornamental container production systems. The two sensor types deployed were load cells and capacitance-based VWC sensors.  Each set of sensors was connected to an eKo Node that communicated with a centralized base station. The nodes transmitted sensor data to the base station once every fifteen minutes. Data was then automatically uploaded to servers via a cellular modem and made accessible using either a website or mobile application. The system was effectively deployed in the following production systems: open-air nursery, pot-in-pot production and retractable roof greenhouse.  Growers valued the ability to identify instances of over-irrigation, which led to several opportunities to refine irrigation practices.  In some situations managers observed improved communication with, and education of their irrigation staff.  Growers shared a concern of cost for implementing this technology on a commercial scale, especially considering the diverse number of plant species and production scenarios that occur at a typical nursery.  Alternative strategies are being considered to reduce the scale at which this system is deployed such as focusing on troublesome crops or to help refine irrigation practices for new and existing crops.