It was Jack van der Voort's father from SchermNed who came up with a self-developed insect netting filter system years ago. It is an alternative to the much better-known harmonica netting system in horticulture.

"We have been working with it for years, but we never really made a big deal out of it," admits Cock's son. Together with Terry and Mark, and the entire team,he now runs the family business. "Initially, it was mainly breeding companies that asked for it. In recent years, we have also been installing the insect netting filter system for many cucumber growers."

Climate

And now, they see at the Westland family business that the insect netting filter system is becoming known in other crops as well. Jack mentions gerbera growers and also tomato growers. "Now that more growers are using it, we are getting new results." Nine years ago, a TNO study was conducted. A patent on the product followed. The research at the time already showed that despite being cheaper than harmonica netting, the insect filter performs just as well as the more expensive product.

"What we have been hearing more and more lately is that growers can continue to cultivate in the same way, even after installing the insect netting filter, both with the settings of the climate computer and mentally. For example, gaps with the windows remain the same with our insect filter. The gap you pull does not contain netting. New settings are not necessary. The temperature rise with the filter is a maximum of 1 degree Celsius. Growers are very enthusiastic about it."

A mesh size of 0.27x0.77 millimeters is chosen in 90 percent of the cases in greenhouse horticulture, but SchermNed now also sees 0.77 x 0.77 millimeters increasingly.

Getting some fresh air

This is evident from the story of plant nursery WPK, which has had the insect netting filter system installed department after department. The positive results, both for keeping out insects and in terms of climate - "when comparing the graphs, we saw no differences in temperature and absolute and relative humidity" - convinced a tomato grower who came to see the nursery to also make the switch to insect netting. "And now we see even more tomato growers making the switch."

The insect netting specialist explains that normally the ventilation window 'scoops' the wind. With harmonica netting, also supplied by SchermNed and more commonly used in new construction situations, the wind passes more freely. "With our insect netting filter system, you still scoop air, thanks to the shape of the netting on the inside of the window. This makes it still possible to create a good climate."

Self-cleaning