Urban metabolism frameworks offer insight into flows of energy, materials, and services in cities, yet tree species selection is seldom treated as a metabolic indicator. In Amman, Jordan, we integrate spatial metabolic metrics to critique monocultural greening policies and demonstrate how species choices forecast long-term urban metabolic performance. Using ENVI-met 5.61 simulations, we compare Melia azedarach, Olea europaea, and Ceratonia siliqua, mainly assessing urban flow related elements like air temperature reduction, CO₂ sequestration, and evapotranspiration alongside rooting depth, isoprene emissions, and biodiversity support. Melia delivers rapid cooling but shows other negatives like a low biodiversity value; Olea offers average cooling and sequestration but has allergenic pollen issues in people as a flow; Ceratonia provides scalable cooling, increased carbon uptake, and has a high ecological value. We propose a metabolic reframing of green infrastructure planning to choose urban species, guided by system feedback rather than aesthetics, to ensure long-term resilience in arid urban climates.

Climate change significantly affects the well-being of urban populations. Thus, there is an increasing need for public green spaces in cities, as biologically active surfaces play a critical role in modifying the urban climate—cooling temperatures and providing shelter. Some institutional gardens, like cemeteries and hospital gardens, are hidden treasures: they are open but excluded from citizens’ mental maps, while usually having a rich green mass. This article aims to explore these hidden green surface elements, presenting their advantages and disadvantages by measuring their local climate effects. Three institutional gardens located in different urban environments were selected for analysis in the sample area of Budapest to explore how the surrounding built-up areas of the city modify the urban climate. The climate analyses were prepared with the ENVI-met climate simulation program. In the case of both hospital gardens and cemeteries, our studies show that their green spaces have great potential to increase the sense of comfort for both users of the green spaces and inhabitants of the neighborhood. In densely built-up urban areas, it is particularly important to involve institutional green spaces in public use, because with appropriate development they can contribute to cities’ adaptation to climate change.