Place de la Comédie, Montpellier: greening and cooling with TreeParker

Montpellier demonstrates with the redevelopment of Place de la Comédie how urban greening can contribute to a climate-resilient future. As part of the ambition to plant more than 50,000 trees and shrubs before 2026, resilient elms were reintroduced to the square and provided with a sustainable tree pit using TreeParker. The project combines cooling, biodiversity and historical identity, and forms an inspiring example of climate adaptation in public space.

The greening of Place de la Comédie in Montpellier symbolises an ambitious urban vision in which climate adaptation, quality of life and biodiversity are central. The French city is strongly committed to a greener and more pleasant living environment and has set itself an impressive target: planting 50,000 trees before 2026. This ambitious target was officially achieved in 2026: ‘Since the start of the initiative, more than 50,000 trees and shrubs have been planted in Montpellier. The goal was reached with the planting of the 50,000th tree at Hypatie school on 13 January 2026.” With this large-scale programme, Montpellier aims to significantly increase the number of shaded areas during heatwaves and create cooling zones that protect residents from extreme temperatures. The ambition is to make the city a resilient, attractive and future-proof environment. The project includes the creation of new parks, additional planting in public spaces and the greening of streets and squares throughout the city.

Due to ongoing climate change, heatwaves are becoming more frequent and more intense. Montpellier is particularly vulnerable to this. Cooling the city is more important than ever. According to a simulation carried out on the 8-hectare Comédie Esplanade project, the perceived temperature in various areas could be reduced by 2°C to 7°C by 2030. This result can be achieved by making the soil permeable, planting additional trees and increasing the presence of water.

This approach is based on the recommendations of the IPCC (Intergovernmental Panel on Climate Change). On the Esplanade, almost 4,300 m² is being greened, particularly through the creation of wide green strips and by planting trees at the base of rows of plane trees. In total, more than 50 additional trees will be planted in the area around the Comédie and the Esplanade. In addition to misting installations, large fountains with refreshing water features will be placed at the intersection of the Comédie and the Esplanade, providing cooling towards the Musée Fabre.

The greening project of Place de la Comédie offers the opportunity to reintroduce the elm, which once occupied a central place in the square. The choice of elm is well considered. For a long time, the elm was the emblem of squares in towns and villages in the south of France. In the 19th century, elms were among the most valued tree species in Montpellier. They were used to decorate the Esplanade and also adorned the Royal Square of Peyrou. The species chosen for the new planting at Place de la Comédie is the Ulmus Lutèce, a hybrid developed by INRAE and resistant to Dutch elm disease. With a height of approximately 8 metres at planting, the elms on the historic square can eventually reach a height of 12 metres. In this way, they will contribute to improving the ecosystem and creating shaded spaces that align with the history of the city.

The reintroduction of elms at Place de la Comédie began in early spring 2023. Each tree was given a considerable soil volume of nearly 75 m³ per tree using the TreeParker system. The trees are equipped with irrigation systems and fitted with moisture sensors to monitor the soil moisture level weekly. To make the planting possible, the upper level of the underground car park was sacrificed. On level 1 of this car park, directly beneath the square, large TreeParker soil cell systems were installed. This unique situation presented numerous challenges, as existing structures, cables and pipelines had to be taken into account. However, thanks to the flexibility of the TreeParker system, these obstacles were successfully integrated. The system is modular and easily adjustable in height, allowing cables and pipelines to be efficiently incorporated without compromising the growing space of the trees.

The TreeParker system consists of linked modules with space in between for a soil composition tailored to the needs of the tree species. This ensures that the trees have sufficient underground space to develop healthily and root without obstruction. By replicating the natural growing conditions of a tree as closely as possible, a sustainable tree pit is created in which trees can grow old healthily even in a highly urbanised environment, surrounded by paving and buildings.

In the summer of 2024, we visited Place de la Comédie to observe the development of the trees. The elms have established well, are in good condition and have a healthy leaf mass. It is now a matter of proper maintenance and giving the trees time to grow into healthy, mature specimens. In this way, they will be able to provide Montpellier with many climate benefits in the future!