Substrate electrical conductivity (EC) measurement is a required Best Management Practice (BMP) for the application of supplemental fertilizers in Florida nursery and greenhouse industries to protect and conserve water resources. The current method of measuring substrate EC is through the Pour-through (PT) procedure, a multi-step method in which representative plants are selected for EC measurement, and a predetermined volume of water is poured on the surface of each test plant. The resulting leachate is collected and EC is determined using an EC meter. This process can be extensive for large-scale nursery production zones, requiring a significant amount of time and manual labor. With the personnel shortages that exist in production nurseries, technologies are needed to improve and optimize EC measurement and recordkeeping so the BMP is effective. This project aims to develop a new, sensor-based method for measuring EC to reduce the time invested by producers compared to the current PT method and provide real-time information on the fertility status of container-grown plants. To achieve this goal, a variety of low-cost, soil-based EC sensors were selected for measuring container substrate EC. Laboratory tests were conducted to evaluate the impact of various environmental parameters on sensor performance and select an optimal sensor for use in this application. A sensor system was designed for field deployment and wireless communication was established to monitor sensor data remotely. A field study is currently being conducted to compare EC data obtained from the sensors to EC measurements collected manually using the PT procedure and develop a protocol for sensor deployment in nurseries. At the end of the experiment, a destructive soil sampling technique will be employed to examine salt stratification within the nursery containers and help determine optimal sensor placement in the pots. This study highlights the need for technology and data-driven methods in modern agricultural practices to address challenges such as production efficiency and personnel shortages.
