Objective – to elucidate creative work of the doctor of biological sciences, Professor Leonid Ivanovich Rubtsov, as an experienced connoisseur of flowering ornamental plants. Material and methods. It was used the historical and scientific methods. Results. It was determined that Leonid Ivanovich Rubtsov, widely known as a dendrologist and landscape architect, actively researched and used flowering ornamental plants in theoretical studies (articles, brochures and books) and practical activities: in creating landscaping projects for floral hill, Mountain Garden, sectors of forsythia and English dogwood of M.M. Gryshko National Botanical Garden of the NAS of Ukraine, which significantly improved created landscape compositions. L.I. Rubtsov was actively involved in the development of proposals for floral design of cities. He also paid much attention to compositions from cut flowers and winter forcing of the shoots of ornamental shrubs. Conclusion. Leonid Ivanovich Rubtsov is a connoisseur of flowering ornamental plants, as evidenced by a number of his theoretical works and practical developments.