Metz: greening with TreeParker at Place de la Comédie and Place de Chambre

In 2020, the French city of Metz realised a remarkable greening project on the historic squares Place de la Comédie and Place de Chambre. Using TreeParker soil cell systems, new trees were successfully integrated into a heavily paved and monumental setting, adding more shade, biodiversity and climate resilience without compromising the historic character of the squares.

Metz has been known for years for its strong focus on greenery and quality of life. The city, which in 2019 was named the best large French city in terms of biodiversity and is among the greenest cities in the country, has no less than 625 hectares of public green space. With more than 53 m² of green space per resident, this is well above the national average. Driven by the ambition to make the city more climate-resilient and attractive, Metz launched an ambitious greening programme for its historic city centre, including the redesign of Place de la Comédie and Place de Chambre.

In 2020, new trees were planted in the historic centre, on Place de Chambre and Place de la Comédie, in locations traditionally dominated by stone and paving. The objective was clear: to create more shade, reduce heat stress and enhance biodiversity, without detracting from the exceptional heritage character of these monumental squares.

For Place de la Comédie, the city opted for the TreeParker system, enabling a tree to be integrated into a fully paved urban environment. Underground, the tree was provided with sufficient root space, water and air, while the square retained its historic appearance. The Tree Root Guiding system, integrated into TreeParker, ensures that roots do not cause surface uplift.

On the nearby Place de Chambre, trees were also added as part of the same greening programme. The plans initially even led to archaeological investigation, as the required planting areas were located in an archaeologically sensitive zone. Preventive excavations by the archaeological team of Metz Métropole revealed unexpected remains from the Roman period and the Middle Ages before the trees could eventually be planted. Here too, two trees were planted using the flexible TreeParker soil cell system to enable optimal root development.

The project demonstrates that climate adaptation and heritage preservation can go hand in hand. Instead of large-scale redesign, a strategy of carefully positioned trees was chosen, providing cooling, biodiversity and a more pleasant public space. In this way, Metz became an inspiring example of how historic city centres can be prepared for a warmer climate without losing their character.