The technology of cultivating on water is fascinating

"A solid belief in yourself and an even greater belief in technology, that’s the formula for Botman Hydroponics, the ultimate floating cultivation system." The company spent more than ten years on development and research. "It was a necessary period for refining and optimising every aspect. Now the real action starts", said Jan Botman, company founder.

Until about five years ago people were still often skeptical to the ideas of crop cultivation on water, but you can’t ignore it anymore. The concepts have been refined and thorough research is being done. Hydroponic cultivation has finally become a reality. Jan: "The technique of hydroponic cultivation grabbed me years ago and it has not let go, I have worked for about twenty years as an exporter of produce, especially overseas.

"I decided I wanted to do something else and I read about the program called "Teelt de Grond Uit” (Cultivation Out of the Ground) from Wageningen UR. In this program, cultivation systems for open-field horticulture are being developed that comply with European regulations for water quality. This is done in cooperation with Proeftuin Zwaagdijk and others. Back then, I had already visited a hydroponic project in Belgium that used gutters. I contacted Wageningen and got on board as an entrepreneur. In the meantime, I was already involved in a program of growing leek on water at the testing company of Applied Plants & Environment in Vredepeel. In 2012 I got more deeply involved."

Crop level sub-climate

"Proeftuin Zwaagdijk conducts applied research and I developed the Botman Hydroponics system. The nice thing is that the further development of the system ran parallel to the tests that were being done. Many other systems of cultivating on water work with styrofoam, for example. I absolutely wanted the materials of my system to be 100% food safe, which is why I opted for plastic. In 2013 I made the first Botman Drijverbak model, for both leaf crops and ornamental plants. After several years of testing and research we gained a deeper insight into how the system works and how crops can grow optimally."

"The nice thing about plastic is that it lets the temperature through, because it doesn’t insulate. Contrary to what is sometimes thought, this offers great advantages: the water that the container floats on can act as a type of floor heating - or as cooling. This allows us to create a sub-climate at the crop level, without the entire room having to be a certain temperature. This is much more sustainable. This system also does not leave any waste. The plastic can be recycled and the plant containers are biodegradable. All components have been thought through in detail in order to achieve the most efficient result possible."

Oxygen-rich water

"Another long-held assumption was that the oxygen content of water was unimportant. The opposite is true. The presence of oxygen is essential for the absorption of nutrients by the plant. I therefore developed a system for this as well, that’s been studied for three years now. All the results indicate that we are on the right path. In oxygen-depleted water, disease also becomes more likely. This is also the biggest risk of cultivating on water. If things go wrong, then a bacteria can spread rapidly through the water, so you have to make sure that it can’t go wrong. We’ve been successful so far.

The next step is to control the water temperature with a heat pump for both heating and cooling. I have been working on this for ten years, but to me it’s really only about to start now. The actual production is going to begin, I'm really looking forward to that. It takes a lot of time and attention to think of every step. I stand up and I go to bed with them. But with a smile. "


"From LivingLab EVERGREEN I made a test setup for Clusius Lab, the practical teaching facility at the Clusius College in Hoorn that allows students to do tests on behalf of entrepreneurs. I facilitate the hydroponics system that students can use to find answers to various research questions. While the system of Botman Hydroponics has my name, I of course can’t do it all alone. I also work gratefully together with different companies and people. Students can make valuable contributions through smaller, very concrete studies. For example, calculating working with heat pumps or researching an idea for supporting the stems of chrysanthemums. Because they naturally go vertical, you need crop support. And even though some studies do not seem that important, often they are very necessary to get a step further. I can imagine that it would be fun as a student if you could contribute to that."


"In the collaboration with organisations such as Proeftuin Zwaagdijk, like now with the EFRO EVERGREEN project, there is a mutual benefit. They offer the location and a number of facilities, but the input of knowledge comes from two sides, just like the sharing and building on it. I am also a client of Proeftuin Zwaagdijk: partly we work together, other things I take care of myself. The most important thing is the link to the experiments: we have already achieved so many good results. I’m also not the only one working on floating cultivation, other parties are working from their approach. And that we meet each other is only a benefit I think.”

Source: "The technology of cultivating on water is fascinating"  HortiDaily (