The rotterzwam team

Meet the inspiring people who are changing the world by doing. One small step at the time.



We started rotterzwam on a hunch in the beginning of 2013. Now we are part of an European wide movement of small scale urban mushroom farmers.

Siemen Cox

Siemen Cox is entrepreneur and an inspiring speaker. He worked in the financial services sector for 15 years when he decided to walk a different path. He became an entrepreneur because he wanted to contribute to a more sustainable society by DOING. He founded rotterzwam and was, together with his business partner Mark Slegers, initiator of BlueCity. in the meantime he is also co-founder of Coffee Based. For each and every one of these companies the saying goes: Impact first.

Mark Slegers

The time of making plans is over. It is now time for DOING and getting into action. The possibilities are available everywhere around us. The opportunities are literally laying on the street. What I did yesterday made me how I am now and do. I see sustainability as an opportunity to make the world better, and to move forward together. Enjoy what is around you and let us keep that for future generations.

Susanne de Graaf

Came to rotterzwam because she just wanted to make the world a bit nicer. After her studies graphic design and entrepreneurship she started to build working experience at rotterzwam and then she decided to stay. Now she is supporting in the many projects that rotterzwam is initiating.


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