Water is a finite and essential resource, and its efficient use is critical, especially in agriculture, which accounts for over 70% of global freshwater consumption. Rural microentrepreneurs often face difficulties accessing efficient irrigation technologies due to high costs and operational complexity. This study presents the development of a low-cost automated irrigation system aimed at supporting small-scale farmers, combining the principles of Industry 4.0 with embedded systems and Internet of Things (IoT) technologies. The proposed system integrates an ESP32 microcontroller with wireless communication and a set of environmental sensors—soil moisture, air humidity, temperature, and rainfall. The firmware was developed in C/C++ using the Arduino IDE, and the system communicates through the MQTT protocol to enable real-time monitoring and control via a supervisory interface. The chosen irrigation method was localized drip irrigation, installed in a passion fruit plantation (Passiflora edulis), due to its efficiency in reducing water waste. A functional prototype was implemented and validated under field conditions, successfully triggering irrigation events based on predefined environmental thresholds. The results indicate that the system operates autonomously and effectively, enabling water savings and better crop management without requiring constant human intervention. The project demonstrates that accessible technological solutions can enhance productivity and sustainability in rural settings, promoting digital inclusion and more efficient use of natural resources in agriculture.