Vertical greenery systems (VGS) are gaining recognition for their environmental and architectural benefits, such as improving energy efficiency, thermal regulation, air quality, and promoting biodiversity in urban areas. Despite increasing interest, research on the role of vegetation in these systems remains limited. The selection of appropriate plant species is crucial as it directly impacts system performance. This review focused on peer-reviewed studies addresses key gaps in VGS by focusing on three main areas: (1) identifying trends and future research directions from academic databases regarding vegetation use; (2) exploring how vegetation can enhance VGS performance through plant maintenance technologies such as mediums, fertilizers, lighting, and irrigation; and (3) identifying key plant species most suited for VGS, with a focus on benefits such as air quality, ecology, energy efficiency, acoustics, thermal performance, and visual appeal. Data were analyzed in ATLAS.ti using systematic coding to identify key variables: plant species traits (life span, type, growth habit/environment), environmental performance (air quality, thermal regulation, water recycling, biodiversity), social benefits (noise reduction, visual quality, education), and economic outcomes (energy efficiency, generation). Research findings suggest that optimizing species selection, understanding plant-environment interactions, and developing practical guidelines are vital for improving the performance and sustainability of VGS, especially in diverse urban climates. By addressing these factors, this study aims to support the advancement of VGS, offering valuable insights and direction for researchers, planners, developers, and those involved in urban and rural planning. © 2025 Elsevier B.V.