I completed my PDC in 2010. The importance of soils was obvious since then, so I started to study on that.

In 2011 I started Sense of humus (in Dutch: Gevoel voor humus). In 2013 I started giving free courses on soil fertility ('humism'), which turned out to be in high demand. Anyone can take the course for free and leave a donation if they want. It has become the main source of income. On average, I get about 500 participants per year on about twenty courses. I also give lectures on a regular basis.

In 2013/2014 I translated 'Teaming with Microbes' by Jeff Lowenfels and Wayne Lewis to Dutch ('Het Bodemvoedselweb'). In 2014/2015, I translated 'Building Soils Naturally' to Dutch ('Bodem in Balans').