Spotlight on innovators: Theo Rieswijk

4 min read - published on December 8, 2019


Theo Rieswijk has been working at Priva since 1992. He’s passionate about control technology and making the way we live more sustainable. Currently, Theo is a proud member of Startup team 42, a startup within Priva. This special team’s goal is not only to save energy, but also to make conditions inside buildings more comfortable. In addition, Theo helps the Phil team study environmental plant data.

How many years have you worked in horticulture, where in the world and in what capacity?

I’ve been working in horticulture for 16 years, all of them at Priva. During my first period there, I helped with the technical introduction and further development of the Connext climate computer. I then began researching several subjects such as plant growth in combination with greenhouse conditions and energy use. In 2008 I joined Priva’s innovation team. My focus shifted away from horti to control technology and the building environment.

Which development has changed greenhouse horticulture the most in the last 10 years?

Twenty years ago, horticultural companies in the Westland were all family businesses. Knowledge, especially regarding climate, was transferred from father to son and stayed within the company. They were very hands-on, focused on their own business and crops. Today there’s been a shift from this artisanal approach to a more business-minded approach. They have to deal with other elements, like contracts with buyers. The horticulture business has become more market-driven. Because there is a need for continuity in the sector, the transfer of knowledge has become important. It will ensure continuity in the sector. I think this transfer of knowledge will be important in the coming period. 

Where do you think the largest opportunity lies to add value for vine crop producers, from a technology perspective?

The opportunity lies in safeguarding and transferring knowledge about horticulture. This contains many elements of operational management: climate, automation of labor, knowledge about growing, and predictability of harvest in terms of yield and quality. 

For me, the grower is always central in horticulture. They are the source of innovation.


Who do you look up to in the industry, either as a mentor or thought leader?

For me, the grower is always central in horticulture. They are the source of innovation. They are willing to take risks, so it’s our job to support them. Growers are really aware of the complexity of what they’re doing. One little mistake and a whole harvest can be ruined. Still, they have the courage to innovate and try new things.  

What attracted you to work with Priva?

Priva’s focus is on energy, food and comfort; important subjects for humankind. In addition, I really love that Priva is a family business. Hats off to the Prins family! They are very open to exploration and innovation. Meiny travels the world to share her story about Sustainable Urban Deltas. I feel very connected to the ambition of the company. It makes me proud to be a part of a bigger story and to make such an impact.

The Netherlands has a great reputation for being the world leader in greenhouse production. Can you identify the key drivers keeping them in this leading position?

There’s a lot of quality knowledge in the Dutch horticulture sector. It’s typical for our sector that the growers are very open in sharing this knowledge. They come together as groups, both offline and online. Because they feel connected, this contributes to making the whole sector stronger. 

There’s a lot of talk about the use of artificial intelligence and machine learning in horticulture, but it’s yet to be widely adopted. Do you think this is due to the lack of proven products, or conservative adoption of new technology within the greenhouse industry?

I don't believe slow adoption is a problem in the sector. The horticultural sector is willing to innovate, but I think the problem is more difficult than predicted. Predicting harvest is not that easy to capture with machine learning methods. You don’t want to just capture and reproduce the ideas of a single grower. You have to draw on broader knowledge. The problem you want to solve is so complex because the growing process is spread over a long time span. Besides that, you have a lot of aspects to consider: labor, climate, disease, incidents and so on. It’s a big challenge to capture this whole process and all the factors in machine learning. But the complexity doesn’t mean it’s impossible or not worth taking on.

The future lies in control and process control. Growing indoors will become more important for urban areas.


You have been instrumental in helping to design a new form of environmental data analysis and optimization — where do you see this ending up? 

What I have done so far with Phil is mainly to look at the growth process of plants. A plant produces sugars under certain conditions, which it then has to distribute between its leaves, roots and fruit. It also absorbs water. By looking at a plant you also gain insight into all the aspects that take place outside the plant. We want to find the correlation between interesting conditions and the results shown by the plant. 

The future lies in control and process control. Growing indoors will become more important for urban areas. For the control needed in indoor growing, you need a strong knowledge of plants. Eventually, you will have ‘templates’ for growing, depending on the conditions of the location of the indoor farm. It’s essential to have strong horticulture knowledge to get the best results, along with consideration of the growing needs and conditions.

What drives you every day, after putting so much energy into the horticulture space?

My drive is to make the world a better place by using the knowledge we have. It’s beautiful to see so much drive in young people — I’m very excited to see that young people are drawn to Priva and love working here.

Care to share?
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Published December 8, 2019


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