Without water, there is no life, but also no greenhouses. It is a great challenge to ensure that every horticultural business can have access to enough good starting water. We must achieve an almost emission-free greenhouse. The last few months, a lot has been written about the emissions of pesticides, which should be limited to ensure the quality of surface water. Innovation is needed in the path towards more sustainable cultivation, and the current research programme Waterproof Greenhouses is sharply focused on this.
Climate change is leading to shorter periods of heavy rainfall, followed by (relatively) long periods of drought. Consequently, it rains less often, but with greater intensity. Not only is that a problem for the drainage of excess rainwater in the area, but also for the availability of water in the rain water basin. We would need to absorb more water in order to have enough for irrigation in the drier periods.
How are we going to achieve this? At the moment, shortages are alleviated with the use of groundwater. If this is no longer allowed in the future, we may lack sufficient irrigation water. The construction of a bigger tank is not always possible, but solutions are currently sought after through several innovative projects. We already heard about the use of Delft Blue Water as (supplementary) irrigation water for greenhouses. In time, this will provide wonderful opportunities for the water cycle also at field level. Another example is the storage of (rain) water in an underground water storage facility.
"Worldwide, it is becoming important to be able to harvest more with less water. Compared to the past, but also to many other countries, we are now already managing to harvest more with less water; it is not without reason that Dutch greenhouses are admired abroad. In any case, we keep trying to move forward in using less water, but more efficiently. Water in the greenhouse should ideally be re-used as many times as possible. Through different projects, we are looking for ways to continue improving this, thus further reducing emissions."
To grow a good product, it is sometimes unfortunately inevitable to waste some water. In current, but also in new studies, and together with other interested parties, we will continue (to) investigate how the purification of waste water can be carried out as effectively and efficiently as possible. As a sector, we want to make targeted investments in sustainable horticulture.