While the extremely dry summer has left its mark on Europe, good quality water has been a source of concern to many European vegetable farmers for far longer. Many tools are in fact available to manage water in the greenhouse in a circular – and therefore efficient and sustainable – way. These methods have now been compiled in one publication: the Fertigation Bible, providing European vegetable farmers with their first-ever overview of the available methods.
“The Fertigation Bible is the tangible result of a wide-ranging European knowledge project known as FERTINNOWA,” says Wilfred Appelman of Wageningen Food & Biobased Research. It is intended for European vegetable farmers who add nutrients to the water in their greenhouses. “We asked some 400 European horticulturalists about the bottlenecks they encounter with water. Salination is a common issue, as is preventing algae from developing in stored water and stopping expensive drip systems from clogging. We ended up with a broad range of questions from the farmers, and the Fertigation Bible describes the best technologies available today to tackle these issues.”
Learning from other sectors
The project, that will be concluded with a three-day conference in Almeria (Spain) from 3 to 5 October 2018, involves dozens of European knowledge partners. Wageningen Food & Biobased Research is responsible for the innovation segment of the project. Appelman: “We mainly focused on what horticulture can learn from technologies that are already widely used in other sectors, such as the dairy industry, chemical industry and energy sector.”
Selectively desalinating water
Appelman illustrates his point with the technology developed by Wageningen Food & Biobased Research for the selective desalination of water. “When closing the water cycle in the greenhouse, plants start to absorb salts like sodium. Too much sodium can be harmful for plants, which is why farmers discharge oversalinated water. In doing so they first have to purify the discharge water as it contains residues of crop protection agents and valuable nutrients. If one could filter out the sodium at the start, the water could continue to circulate and maintain its quality. This would prevent emissions and keep valuable nutrients in the system. In addition to being sustainable, this also has economic benefits.”
Clean water via membrane distillation
The Fertigation Bible describes a variety of innovative methods. Appelman mentions the technology of self-cleaning floors which is already widely used in hospitals. “We are working on a floor that is flooded to prevent the emission of crop protection agents and nutrients.” Another example involves the production of clean water via membrane distillation using solar or residual heat. This new technology attracted a lot of publicity this summer.
From paper to practice
“The goal of the Fertigation Bible is to help European farmers implement smart measures that will allow them to use water in a more efficient and more sustainable way,” Appelman explains. “All the available knowledge of possible measures has now been clearly described in one document for the first time. In addition to this voluminous publication, all technologies are also available in practical factsheets and detailed manuals. What helps is that all knowledge partners in the project each have a substantial network, making the step from paper to practice that much easier.”
Parties with ideas for new developments who are interested in exploring whether they would be applicable in practice are more than welcome, Appelman states. “This is the ideal network to discuss the feasibility of new concepts.”