Sika joins World Green Infrastructure Network

The global green infrastructure community is saddened by the loss of Professor Nigel Dunnett, who passed away on April 26, 2026, at the age of 63. As a visionary horticulturalist, author, and Professor of Planting Design and Urban Horticulture at the University of Sheffield, Nigel was one of the world’s most influential voices in redefining the relationship between nature, architecture, and urban planning. At the World Green Infrastructure Network (WGIN), we honor his extraordinary legacy. Nigel did not just design gardens; he pioneered a philosophy that transformed urban spaces into dynamic, climate-resilient, and living ecosystems. Nigel was actively involved with the World Green Infrastructure Network (WGIN) as the UK representative in WGIN. Nigel participated in several congresses of the network, among others in Toronto in 2009, Mexico in 2010 and in Nantes, France in 2013. He advanced the field of knowlegde and practice in urban biodiversity through his guidance of several PhD candidates and the legendary internationally inclusive conferences in Sheffield. A Leading Voice for the Green Infrastructure Community of Practice Nigel Dunnett was central to the transformation of the green infrastructure movement, shifting the global professional focus from sterile, hard landscapes to biodiverse, high-performing “soft” infrastructure. He bridges the gap between rigorous ecological science and breathtaking artistic design, proving that urban greening could be simultaneously wild, functional, and deeply beautiful.His contributions to our community of practice are monumental: A Pioneer of Naturalistic Planting: Alongside his long-time collaborator James Hitchmough, Nigel pioneered ecological, seed-based naturalistic planting. He challenged traditional, high-maintenance landscape management by proving that diverse, low-input plant communities could thrive in harsh urban environments. Transforming Public Consciousness: His high-profile masterworks brought the concepts of urban biodiversity and green infrastructure into the global spotlight. From the spectacular, climate-adapted expanses of the Queen Elizabeth Olympic Park to the Tower of London “Superbloom” and the Barbican Beech Gardens, Nigel showed the world what a green city could truly look like. Sustainable Urban Drainage (SuDS): Nigel was a fierce advocate for integrating water management into the urban fabric. His work on the Sheffield “Grey to Green” project remains a gold-standard blueprint for how cities can use bioswales and urban vegetation to mitigate flooding while enhancing public life. Author: Nigel authored Planting Green Roofs and Living Walls (co-authored with Noël Kingsbury) Dunnett and Kingsbury shifted the narrative on building integrated green infrastructure by arguing that green roofs and living walls should be designed as dynamic, highly biodiverse, and aesthetically pleasing ecological systems. Together with Andy Clayden Nigel co-authored Rain Gardens: Managing Water sustainably in the Garden and Designed Landscape. Following the same philosophical line as his work on green roofs, Nigel revolutionized how landscape architects and garden designers approach urban hydrology. Educator and Innovator: Beyond his books and research papers, he founded the social enterprise Pictorial Meadows, democratizing ecological urban design by making wildflower meadow systems accessible to municipalities worldwide. As an educator, he inspired multiple generations of landscape architects to prioritize ecological integrity. Healing Through Nature: The Aberdeen Royal Infirmary Roof Garden While Nigel’s grand urban masterplans won international acclaim, my personal favorite of Nigel’s many contributions to our field is the role he played in the creation of The Robertson Family Roof Garden at the Aberdeen Royal Infirmary. The project originated from Nigel’s gold medal-winning RBC Blue Water Roof Garden at the 2013 RHS Chelsea Flower Show. Rather than letting the installation disapear after the show, Nigel collaborated with the hospital’s Chaplin James Bell Falconer to adapt the design and installation into a permanent, 24/7 therapeutic sanctuary in the heart of the hospital. Opened officially by Queen Elizabeth II in 2017, the garden represents a pinnacle of biophilic, inclusive healthcare design. Nigel engineered the rooftop to be entirely accessible, ensuring that even critically ill, fully ventilated patients from the intensive care unit could be wheeled outside to experience the open air, the rustle of grasses, and the scent of trees. The Aberdeen roof garden stands as a powerful testament to Nigel’s belief that access to nature is not a luxury, but a fundamental human right—and an essential component of clinical recovery and psychological restoration. A Lasting Legacy Nigel Dunnett’s work altered the trajectory of modern landscape architecture. He taught us that urban nature should not be merely decorative, but an active, spontaneous, and healing force woven deeply into our buildings and streets. The World Green Infrastructure Network extends our deepest condolences to his wife Marta, sons Alex and Jack, colleagues, and the countless students and professionals he inspired.