During the Water Weeks in May some 175 growers were informed about promising solutions for restricting the emission of nutrients and plant protection products. Together with their partners, researchers of Wageningen UR Greenhouse Horticulture presented the preliminary results obtained in the project Greenhouse Horticulture Waterproof.
Discussion about the authorisation of crop protection products and the European criteria for water quality make emission restriction an extremely urgent issue in the greenhouse sector. In the project Greenhouse Horticulture Waterproof researchers are taking two lines to restrict the emission of nutrients and crop protection products. The first line investigates the possibilities to reduce the amount of discharged drainage water and the frequency of discharging. The second line is looking at water treatment and the possible commercial utilisation of the waste water remaining to be discharged.
Responsible water reuse
Some cultivations are showing growth inhibition in the form of crop quality loss. This is an important reason for growers to discharge drainage water. Bram van der Maas and Steven Driever, researchers at Wageningen UR Greenhouse Horticulture, are together with Priva, Groen Agro Control and Fytagoras working in a project that is to provide insight into the causes of growth inhibition and into the possibilities to prevent these.
At the same time, Chris Blok of Wageningen UR Greenhouse Horticulture is investigating whether fertilisation can be optimised by increasing the reuse of drainage water where ion-specific measurement and application of improved control systems are among the options. Waste water treatment seems to offer chances as well. TNO is, together with Wageningen UR Greenhouse Horticulture, investigating the possible options for treatment as well as possible uses for the waste product that remains after treatment.
More insight into growth suppression
During the Water Weeks it was shown that growers can now already start with implementing quite a number of measures. Project leader Ellen Beerling explains: “Growers indicated that they want more insight into the extent to which growth inhibition is playing a role in drainage water recirculation to further increase the possibilities of drainage water reuse in the future. More insight is also required into the costs and possibilities of technical applications that are currently being investigated.”The Water Weeks were made possible by Product Board for Horticulture, Ministry of Infrastructure and Environment, Hagelunie, the water control boards Delfland, Schieland and Krimpenerwaard, Peel and Maasvallei, and Bruine de Bruin BV, Priva B.V., Stolze B.V., Hellebrekers Technieken B.V., Bayer, Syngenta and Basf. The project is carried out by Wageningen UR Greenhouse Horticulture together with TNO, Fytagoras, LTO Groeiservice, and Groen Agro Control.