Although digital technologies on farms bridge the productivity‐sustainability gap, they are not yet widely adopted. Familiarising farmers with digital systems is as important as developing advanced technological platforms: As farmers become accustomed to and feel in control of digital systems, they will find it easier to accept, adapt and keep pace with technological developments. This article describes the design and implementation of a flexible, scalable, easy‐to‐use and extensible IoT embedded system to control sprinkler irrigation in an outdoor Thuja conifer nursery in an automated mode and under varying weather. Irrigation is controlled by Mamdani Fuzzy Inference Logic based on rainfall prediction and real‐time monitoring of the plants. The IoT system provides a control dashboard and offers three operating modes: manual, automated or scheduled (daily, weekly, and monthly). The system is robust in the event of a power outage or loss of connectivity. The code is available on GitHub. Sensors, solenoid valves, Raspberry Pi microcontrollers, fuzzy logic systems, a web interface and a cloud service create a sustainable solution that makes water use more efficient, creates a healthy environment for crops (using just the right amount of water), makes life easier for farmers, and exposes them to the benefits of the IoT.