The green façade has been an integral part of the concept for the Kö-Bogen II commercial and office building ensemble designed by Düsseldorf architect Christoph Ingenhoven from the very beginning. The hornbeams are not only an architectural highlight, but also an important factor in climate protection; they fulfil ecological functions and thus contribute to the sustainability of the Kö-Bogen II in the city centre of Düsseldorf.