Water. It’s essential for everything that grows and blooms anywhere in the world. And of course greenhouse horticulture is no exception. But with the advent of new, improved cultivation techniques and innovations, our sector is perfectly placed to use the good quality water we have at our disposal sparingly and carefully.

Columnist Herbert Stoker in South Africa has already written about the water problems in the Cape Town area in the south-west of the country, which are forcing growers to revisit the way they use water. As a result, drip irrigation is very much on the up. And even though there is plenty of rain in other parts of southern Africa, filling farmers’ reservoirs and gardeners’ water butts, attention needs to be focused on water there too. The burning issues are: How do you handle water flows to which nutrients have been added and which contain crop protection residues? And how will this impact on the soil, flora and fauna, and human health?

Here in the Netherlands, water treatment is one of the key issues facing greenhouse growers. As of 1 January this year, all Dutch growers are required to treat their water before discharging it into surface water. They can do so using their own fixed water treatment unit or a mobile unit, or they can use shared facilities. The third option is a closed system in which the water is reused and not discharged at all. This government measure currently only relates to crop protection products, but fertilisers are due to be added over the next few years.

In the European Union, environmental commitments such as these are still not harmonised but every member state will have its own targets and regulations in this area. Some countries have gone quite a bit further than the Netherlands and others are set to follow soon. Although the 1 January 2018 deadline was known about for some years, many growers only took action at the last minute. Researchers, advisers and suppliers delivered a masterpiece which growers on various continents can benefit from. After all, as Bob Dylan once said, “The Times They Are a-Changing”.

text: Roger Abbenhuis.