Behind the facades of Foam lies a charming city garden, which usually remains hidden from visitors and passers-by. The garden was designed in the early 1950s by none other than garden architect Mien Ruys (1904-1999). In 1993, Els Proost was asked to redesign the garden for the museum, then the Dutch Design Institute, so that it could be used for openings and exhibitions and to preserve the heritage for generations to come.

When Els Proost started working in the overgrown garden in 1994, she came across several still usable elements dating back to Ruys' design. Aware of the garden's special history and the legacy of Mien Ruys, Proost incorporated as many of these original elements as possible into her own design. As a homage to Ruys, she retained the elm on a rise and the two hedge blocks of holly.

Ruys played an extremely important role in Dutch garden design, while Proost’s design is very valuable in its own right. The lines in Proost’s design harmonise with the rear facades and open garden spaces. Her design was also geared toward receiving large groups of people, for instance at openings or for conferences, while visitors were meant to be able to move around and enjoy the monumental garden in every season of the year.