Being responsible for the Dutch railway network and the train stations throughout the country, ProRail is strongly committed to sustainability. Blooming Buildings have prioritized the integration of greenery as a catalyst for biodiversity, climate adaptation, and the creation of inviting environments. One of the pilot projects took place in the courtyard garden of ProRail’s head office, located in the historic national monument Inktpot in Utrecht.

Although the courtyard was already planted, it lacked biodiversity – except for bats, there was no other animal life, not even birds. As an experiment, they redeveloped a section of the space while working within the existing contours and concrete slab flooring. To introduce more greenery, they strategically placed plant containers where needed.

The Inktpot is the largest brick building in the Netherlands. The design of the courtyard garden blends seamlessly with the iconic 1921 building, with planting that reflects the architecture in both form and color. Together with landscape designer Harry Pierik, they decided to embrace this heritage. They discovered that the choice for the entrance planters aligned with the planting originally selected by architect George van Heukelom. To further honor history, they reintroduced Parthenocissus – a characteristic plant of the Amsterdam School architectural style.

Despite the deep shades, the garden thrives with an abundance of plant life and color, carefully curated to complement the building’s handcrafted stone and glazed interior. The blue-grey hues of the belltower’s grand mosaic also served as inspiration. To emphasize the building’s verticality, they used the buttresses as anchor points for plant containers, allowing cascading greenery to create a visual connection with the ground level.

The courtyard garden is a stunning example of biodiversity in urban spaces. It has become a living testing ground for designers, project managers, and stakeholders, as well as a frequent destination for ecological tours. As Reinout Wissenberg, ProRail’s Director of Sustainability, says: “There is always something new to discover. Something in bloom, a new color, something growing along the building. It’s a place where employees can experience what nature is and how it effects you”.