Peter van Bodegom on sustainable horticulture
Dutch greenhouse horticulture is a world leader when it comes to innovative capacity and sustainability, but ‘the challenges are great in terms of energy, water, environment and biodiversity,’ says Peter van Bodegom, coordinator of AgriFood at the Centre for Sustainability of the Leiden, Delft, Erasmus strategic alliance. ‘We are good at connecting global developments and regional interests, so we can help horticulturalists in the Netherlands with the transition to an even more sustainable greenhouse industry.’
In recent months, greenhouse growers – and many others – were once again forced to face the facts. Geopolitical developments caused the price of gas to quadruple. This made it all the more clear that greenhouse horticulture must look for other sources of energy. Several companies have already switched to geothermal energy (heat from deep underground), while others are experimenting with the temporary storage of (solar) heat.
‘Another challenge is the greater probability of prolonged drought as a result of climate change,’ says Van Bodegom, Professor of Environmental Biology at Leiden University’s Institute of Environmental Sciences. ‘How to ensure the availability of sufficient, fresh water during those periods? In addition, the sector still has to deal with the leakage of pesticides into ground and surface water. The environmental pressure that this causes calls for more-sustainable crop protection, for example, by making even greater use of biological control.’
The latter ties in nicely with another challenge: to improve biodiversity within greenhouse horticulture. Many horticulturalists prefer to see neatly mown grass around their greenhouses because they are afraid that lusher vegetation will lead to more insect pests in the greenhouse. Van Bodegom: ‘We are working with a Community of Practice of greenhouse farmers to develop an alternative to the short-mown grass. Which vegetation will promote functional biodiversity, with species that attract pest controllers? It’s really interesting. The horticulturists are experimenting, real field trials in other words, and our students will be evaluating the impact.’
The underlying question is where we want to go with Dutch greenhouse horticulture. Van Bodegom: ‘The sector is now a supplier of bulk products, such as tomatoes, cucumbers and peppers, mostly for export. But it is also an exporter of innovations, i.e. new varieties and smart technical systems. The question is whether it can continue to fulfil both roles. I can imagine that the sector chooses to become the testing ground of the world by focusing on developing and exporting sustainable innovations and knowledge, while bulk production takes place elsewhere.’
When we ask him what greenhouse horticulture in the Netherlands will be like in ten years' time, Van Bodegom says he doesn't want to pin himself down to one scenario. ‘However, there are a number of recurrent themes. I’ve already mentioned energy, water, the environment and biodiversity, but there is also the question of how we can grow even healthier products, which have a high nutritional value and are tasty too.’
There are several possible answers to this question. ‘One interesting development is vertical farming,’ says Van Bodegom, ‘a completely closed cultivation system under artificial light, which reuses water and fertilizers, and uses little or no pesticides. The productivity is very high because you can grow in several layers and harvest several times a year. The question is how to fit such closed farms into the region.’
Another possibility is open sustainable greenhouses that are optimally integrated into the ecological and social environment. ‘The biological control in the greenhouse is supported by the functional biodiversity outside. Water consumption is coordinated with the environment, for example by capturing peak discharges to be used as irrigation water later. Solar panels on the greenhouse provide electricity to the surrounding area and excess heat is used for homes and buildings in the area.’
‘The combination of students from different programmes makes it possible to integrate more-practical knowledge with more-conceptual knowledge. This increases the chances of practical solutions that are also sustainable in the long term..’
The activities of the Centre for Sustainability are not limited to philosophising about the future of greenhouse farming. The Centre belongs to a number of networks – or rather, one large network with several nodes. One of those nodes is the ACCEZ programme, which stands for ‘Accelerating Circular Economy Zuid-Holland’. This partnership between the province of Zuid-Holland, the LDE Alliance, Wageningen University & Research and the VNO-NCW employers’ association focuses on developing knowledge as the basis for policy to accelerate the circular economy in Zuid-Holland.
Another node is the World Horticultural Centre (WHC) in Naaldwijk, an important meeting point for the business community and as such a source of research and educational questions. Van Bodegom: ‘Together with InHolland University of Applied Sciences and the “green” Lentiz secondary vocational education (MBO), we have started a learning community that connects students to companies to help them to solve problems they encounter. The combination of students from different programmes makes it possible to integrate more-practical knowledge with more-conceptual knowledge. This increases the chances of practical solutions that are also sustainable in the long term.’
Down to earth
That combination of conceptual and practical thinking is illustrative of the role the Centre for Sustainability wants to play. Van Bodegom: ‘On the one hand, we want to contribute to the development of an integral vision on the future of the entire chain, from supplier to consumer. On the other hand, we try to be down to earth, to provide concrete answers to the questions that parties in the supply chain are struggling with.’
A major advantage here is that the expertise of Leiden, Delft and Erasmus is well aligned. Van Bodegom: ‘In Leiden we emphasise the environmental and biodiversity impact of the entire chain. In Delft the emphasis is on the “translation” of that systems approach into technical systems, while Erasmus concentrates mainly on the business perspectives. In this way, we can make a solid contribution to a resilient greenhouse horticulture sector in Zuid-Holland that is prepared for an uncertain future.’
This article appeared in the magazine of Leiden-Delft-Erasmus Universities, a partnership between the three universities in the province of Zuid-Holland. Read the full article here.