With the global population projected to reach 9.1 billion people by 2050 there is a need to develop highly efficient agricultural systems that can reliably maximize crop yield. Precision Agriculture (PA) systems enabled by the Internet of Things (IoT) offer a potential solution through improvements in labor, resource, and time efficiency to improve agricultural output. PA systems enable this by providing a detailed understanding of the state of the field (e.g., soil moisture, pH, temperature, etc.) so that these resources can be properly deployed spatially and temporally. To realize these systems, sensors that give information about the state of the field are required. However, for the technology to be scalable and practically implemented, these sensors must balance performance and cost. These requirements limit the materials and methods that can be used to develop the technology, including many that are common in modern sensors. Additionally, the challenge of biocompatibility and biodegradability must be addressed.In this work, materials and manufacturing processes are developed to realize a passive RF soil moisture sensors. In the first part of this thesis, a fabrication process for a fully biodegradable nano cellulose infiltrated paper (NCIP) composite substrate is presented. By using small quantities of cellulose nanofibrils (CNF), we are able to planarize the surface of a pulp-based cardstock paper to achieve smooth surfaces that are suitable for the fabrication of electrical structures. Next, the hygroscopic properties of cellulose are leveraged to develop a capacitive sensor that utilizes the substrate as the sensing mechanism. By utilizing screen printing, repeatable capacitive structures with a high degree of fidelity are able to be produced. The ability to detect both humidity and soil moisture over a wide range is demonstrated. Additionally, sensor cycling and repeatability is shown, a key requirement for in field application. Finally, packaging of the sensor is explored, with natural wax materials explored to realize a fully biodegradable sensing system.