Nature-Based Solutions: Green and Smart Façade with an Innovative Cultivation System for Sustainable Buildings and More Climate-Resilient Cities

To address the challenges linked to climate change, rapidly increasing urbanization, and food security necessity, this study explores the potential of smart, low-cost innovative cultivation systems for modules on facades as nature-based solutions (NBSs) to improve building energy efficiency, urban food production, and sustainability. Innovative cultivation systems were studied and implemented in the horizontal experimental setup, with a focus on sub-irrigation techniques with terracotta pots, ozonated water, and IoT use. The best eco-smart irrigation system was selected considering both plant growth and the water savings obtained (up to 57.14%) in comparison to the traditional method. With the implementation of this system, a vertical green module (VGM) was designed, allowing for efficient distribution and water savings. The positive effects in terms of temperature reduction and energy behavior were validated by comparing two office rooms: one without VGM and the other with VGM in a Mediterranean city. The drop in internal temperatures achieved was up to 3–4 °C during the hot days of the experimental campaign. The uptake of this low-cost and smart prototype can be useful to support the enhancement of energy-efficient, eco-sustainable, and self-sufficient buildings and urban spaces, contributing to creating more climate-resilient cities and promoting sustainable urban agriculture.