<![CDATA[The development of agricultural technology enables the application of microcontroller-based systems to support crop cultivation, including fertilization. In practice, farmers often don’t follow recommended fertilization schedules, causing delays that reduce optimal plant growth, and fertilization still done manually by taking fertilizer from a container and spreading it onto the growing media, making the process dependent on human labor. Water spinach selected as the research object because its uniform stem and leaf structure support consistent pot positioning. Study aims design, build, test an automatic fertilizing device for water spinach, with the research limited to developing and validating the device’s functional performance without automatic dose measurement. The research methods include hardware and software design. The hardware consists of the device frame, an ESP32 as the main controller, an L298N motor driver, an ultrasonic sensor for pot detection, a servo motor for opening the fertilizer outlet, and a DC motor to rotate the impeller for fertilizer distribution. The software was developed using the Arduino IDE with a control system accessed through a local web server, allowing users to adjust detection distance, motor speed, servo angle, and number of pots. Test results show that the device operates as designed, successfully detecting pots, activating the servo, and running the DC motor. The device dispenses approximately ±0.62 g of fertilizer with an 80% success rate across five pots in two repetitions, indicating that integrating the ESP32, ultrasonic sensor, servo motor, and DC motor can support the development of an automatic fertilization system for water spinach plants.]]>
