This article proposes a new low-cost LoRaWAN Power Switch system for intelligent agricultural applications with the aim of reducing labor costs and improving water consumption in irrigation. As an example of testing this controller, the irrigation scenario of the Center for Agricultural Sciences (CCA) of the Federal University of Piauí (UFPI) was used. The proposed methodology was divided into two stages, namely, the real implementation of the IoT devices with the Radioenge LoRaWAN and LoRa ESP32 modules by Radioenge Company and Espressif Systems respectively, as well as the study and analysis and comparison of the network parameters of the LoRaWAN architecture for both devices in different points identified as possible Smart Farming scenarios. The performance evaluation was carried out based on measurements of a real Non-Line of View (NLOS) scenario. In this assessment, factors such as distance between nodes and different scattering factors (SF) were considered. In addition, the received signal strength indicator (RSSI), the signal-to-noise ratio (SNR) and the packet loss rate were analyzed. The results of this study show a new low-cost long-range device, as well as the feasibility of using the technologies employed for Smart Farm applications up to 1.1km range from gateway device for this scenario.