Waterproof Flower-Bulb Cultivation

The bulb cultivation sector in the Netherlands is an intensive user of plant protection products and nutrients. As such, it contributes to the deterioration of surface water and groundwater quality, to the point where the objectives of the Water Framework Directive (WFD) cannot be achieved. Additional measures need to be taken similar to the initiatives surrounding the Activities Decree for greenhouse horticulture and the bulb cultivation sector. The Royal General Bulb Growers’ Association (KAVB) wants to actively dedicate itself to this end.

The direct reason for this project is that different bulb growing companies in the Province of North Holland want to invest in innovative and sustainable techniques, partly in view of possible tightening of the legal and regulatory framework. The Hollands Noorderkwartier Water Authority (HHNK), as a water manager, aims to promote emission reduction measures in collaboration with partners, and to help realise sustainable water concepts in practice. Other participating Water Authorities are pursuing similar objectives.


This project begins with the conduct of an inventory of the quality of runoff water at the bulb companies. An average composition of ‘Reference Water’ will then be agreed in consultation with growers, controllers and the responsible authorities. Laboratory tests will determine which technology achieves a desired degree of degradation of plant protection products (PPPs). The most promising technologies will then be pilot tested under different operating conditions at flower-bulb companies.


In this project we will acquire insight into the composition of runoff water and into the solutions aimed at degrading PPPs to the degree desired. In an initial stage, an inventory will identify the relevant water streams and associated compositions. This will provide the basis for determining a ‘Reference Water’, which will then be used in laboratory experiments. Lastly, pilot research will be carried out onsite at the growers.


  • Determine a ‘Reference Water’ for flower-bulb companies.
  • Demonstrate which technologies can degrade PPPs in the flower-bulb sector to the degree desired.
  • Disseminate the research results through presentations and reports, so that growers understand the applicability of the technology. They will then make investments appropriate to their local situation, which will result in an improvement of the water quality in the surrounding environment.