Fine-grained Soil Moisture Monitoring with PLUTO

Controlling soil moisture is crucial in optimizing watering and crop performance, particularly for crops with high water demands such as Kiwi. Monitoring and simulating soil behavior are two key approaches to understand soil behavior. Proximal sensors are the most reliable way to monitor soil moisture. While in the past sensor costs limited their adoption, the progressive cost reduction makes now possible to properly capture moisture dynamics in the soil volume occupied by roots. Physically-based numerical models can be used to further understand soil moisture dynamics, but solely in an off-line manner due to their time-consuming simulations. We introduce PLUTO, a cost-effective solution that, starting from sensor data, leverages both Physically-based and machine learning models to build on-line moisture profiles for long-term watering optimization. PLUTO, relies on bi/tri dimensional sensor grids that proved to largely overcome the accuracy of previous profiles obtained with traditional sensor layouts. Besides, we provide an analysis of sensor importance that takes in consideration the trade-off between accuracy, number, and position in order to suggest a smart placement.