A Systematic Review of Vertical Greenery: Environmental Impacts, Architectural Innovations, and Future Directions

Vertical greenery is increasingly applied in modern cities for environmental improvement and landscape enhancement. Given the insufficient coverage of recent developments in research and practice by prior reviews, this paper conducts a systematic review based on literature from Web of Science and global patent databases following PRISMA guidelines, with CiteSpace used for bibliometric analysis. This study summarizes the theoretical achievements of vertical greenery in ecological environment, building energy efficiency and technical materials. It also analyzes practical innovations via patent mining—a new supplement compared with traditional reviews. The environmental impacts of both outdoor and indoor vertical greenery are elaborated on: outdoor systems improve urban microclimate, noise control and air quality; indoor systems enhance indoor comfort, air purification and people’s mental status. Current innovations are categorized into structure and equipment, intelligent management, and social–cultural values. The outcomes of this work offer practical guidance for the design, construction and maintenance of vertical greenery in real projects. This paper also identifies future research priorities for the long-term development of vertical greenery.