Over the past few weeks, anyone crossing the Veemarkt will have watched this previously grey square slowly turn green. Through a combination of a temporary "walking forest" and seven larger trees in movable planters, this heavily paved space is becoming a summer garden with 85 m² of extra greenery. It's one of several local experiments Mechelen is running as part of GreenDense, the Interreg North-West Europe project exploring how dense, paved urban spaces can become greener, cooler and more welcoming places to meet.
A forest that walks
The walking forest is an initiative of the Flemish Association for Public Green (VVOG), made available to the city and installed by Pro4Green in collaboration with VLAM vzw. It's a temporary installation of varied planting baskets and smaller trees that will spend the season, from May to October 2026, on the Veemarkt and nearby locations. Because the whole arrangement can be lifted and repositioned, the greenery quite literally walks through the city.
Adding 57 m² of green on its own, the walking forest brings together four tree species in different shapes and sizes - hornbeam, honey locust, plane and Persian ironwood - for a naturally layered look that offers welcome shade and cooling. Beneath them sits a richly varied understorey of ornamental grasses, ferns and more than thirty species of perennials, with catmint, coneflower, sage, marguerites, autumn sunflowers and foxglove among them, keeping the square in colour through the season while drawing in bees, butterflies and other pollinators. Three large seating elements invite visitors to slow down and enjoy it.
"A walking forest is the perfect test for a greener Veemarkt," says Filiep Bouckenooghe, director of VVOG. "Not with plans on paper, but by experiencing for yourself what extra trees and greenery do to the square."
Planters that stay, and store water
Alongside the temporary forest, seven larger trees have now been placed in planters that will remain on and around the Veemarkt for good, together with the walking forest forming a single green whole of 85 m². Three of the planters double as benches, keeping comfort and connection at the centre.
The planters do more than hold trees. "They're a flexible way to bring extra green into the city, and each one has an integrated water buffer," explains Patrick Princen, Mechelen's Alderman for Biodiversity. "Every planter can store around 510 litres, giving a total of more than 3,500 litres. That keeps the trees supplied even during warm, dry spells and makes for a more climate-robust square." The planters hold two river birches, two hornbeams, a London plane and two black alders, the alder a tough, native species well suited to warmer, paved surroundings.
Part of a bigger picture
The Veemarkt is just one piece of Mechelen's work within GreenDense. Across the city, the project has also brought new planting beds to the Groot Begijnhof, de-paving and greenery to the Tessenstraat, extra trees to the Dageraadstraat, a Tiny Forest to Caputsteenpark, and small green meeting spaces to the Heihoek.
"GreenDense lets us test new ideas in different places across the city," says Princen. "From temporary greening to de-paving and new trees, every project contributes to a cooler, more biodiverse and more pleasant city."
By showing that even a square sitting on top of a car park can become a green, sociable place to gather, the Veemarkt offers a small but telling example of the GreenDense mission in action: proof that with a little creativity, the densest corners of our cities can still make room to breathe.
