This study presents the development of a cloud‐based, automated variable‐rate fertigation system by modifying an existing hose–reel irrigation machine (HIM). A 46‐m‐wide HIM spraying boom was segmented into four independently controlled sections, and a 300‐L fertiliser tank was mounted on the spraying cart to deliver liquid fertiliser directly into each section line. A control system, programmed in C#, was designed to automate...