The study investigates the improvement of urban ecological infrastructure via urban and peri-urban forestation initiatives. The study focuses on Blue and Green Infrastructure (BGI) in vulnerable urban areas as a relevant solution to fostering sustainable development and addressing climate change adaptation and mitigation. By integrating multi-criteria spatial analysis and statistical models, the study develops a replicable procedure to identify suitable areas for BGI interventions, ensuring optimised use of financial resources and maximising environmental, social, and economic benefits. The procedure is aimed at organising the information required for implementing the Geodesign process in the context of defining strategies for adaptation to and mitigation of climate alteration. It is applied to a case study in Sardinia, Italy. The study’s findings demonstrate the relevance of the procedure to the spatialisation of public policies, enabling evidence-based decisions in the context of integrating mitigation and adaptation strategies into urban regeneration and sustainable development plans.