Vertical greenery systems across climate zones: a climate-differentiated performance review and SDG contribution framework

Purpose Vertical greenery systems (VGS) are increasingly deployed as nature-based solutions in cities. Yet, their performance varies substantially with climate, and their contribution to the United Nations Sustainable Development Goals (SDGs) remains poorly specified. This leaves practitioners without a defensible basis for climate-appropriate specification. This paper synthesizes peer-reviewed evidence to characterize VGS performance by climate and develops a framework linking that performance to SDG targets across six Köppen-Geiger climate zones. Design/methodology/approach In accordance with PRISMA guidelines (Moher, 2021), a systematic literature review was conducted. Web of Science and Scopus were searched for English-language articles published between 2015 and 2025. After four screening stages, 194 studies were retained for the final analysis. Studies were grouped by Köppen-Geiger classification: tropical (Af/Am), hot-arid (BWh/BSh), Mediterranean (Csa), humid subtropical (Cfa), oceanic (Cfb) and continental (Dfa/Dfb). A complementary bibliometric analysis used VOSviewer to map 975 keyword nodes, revealing 21 thematic research clusters. SDG contributions were mapped using the UN Global Indicator Framework. Findings VGS deliver surface temperature reductions of 5–20°C and cooling energy savings of 15–60%, with tropical and hot-arid climates achieving the strongest performance. SDG alignment is most robust for SDGs 3, 7, 11, 13 and 15. Climate-specific trade-offs are most critical in hot-arid zones, where irrigation water demand can offset SDG 6 and SDG 13 gains unless greywater recycling is integrated. A climate-responsive design matrix and SDG contribution table are developed to guide implementation. Originality/value While prior work has linked VGS to individual SDGs, this is the first systematic review to stratify VGS performance by Köppen-Geiger climate zone while explicitly identifying SDG trade-offs – notably the SDG 6–SDG 13 tension in hot-arid deployment – supported by bibliometric evidence of the field's intellectual structure. The resulting framework addresses the gap between aggregate performance reviews and the climate-specific, practitioner-oriented guidance required for equitable global deployment.