Chrysanthemum grower Fred van Paassen has equipped his new 4-hectare greenhouse with a PARperfect climate screen.
"It is an extra tool for us to control the crop properly," says Jan van Paassen, who made the well-considered choice for the new screen. "We are delighted with that screen fabric."
Chrysanthemum - Ludvig Svensson
The family business is named after his father, Fred van Paassen, says son Jan from the new greenhouse in Wervershoof, North Holland. "My father has been in the business for almost forty years. He started in Schipluiden, but by doubling the acreage each time, he moved towards Andijk and Wervershoof."
An old neighbor's garden was demolished and found suitable as a plot for a new location. "We were looking for an expansion at a location that suited us well. Length and width proportions and available electricity capacity were important criteria," Jan outlines the situation.
PARperfect
A blackout screen is a must for a chrysanthemum nursery. The choice for the fabric type Obscura 10070 FR WB+B was quickly made. "Important to darken, shorten day length," explains Jan. "We did want a second screen to save energy, but then what is the added value in the summer? When we came across the Harmony PARperfect for the lower screen, we saw the benefits of diffused light. Now we have diffused light 'on demand' in summer because the screen 'scatters' sunlight over the crop. That was a decisive factor," says Jan, explaining his choice for PARperfect.
Shadow-free hanging
During the purchase process, we discussed the finishing of the screen installation many times. Dave Boer of installer Huisman Scherming explains that those discussions led to a new technique called 'shadow free hanging.' "On the partitions, there are no blackout strips. That's where the canvases overlap, so no sealing strips or flaps are needed." Jan is enthusiastic about this application, which Huisman Scherming first applied on a large scale at van Paassen. "They did an impeccable job with that."
Jan mainly uses the canvases against each other. "In this way, we play with the amount of light we allow. The flowering crop has little evaporating power in the sun. The whole crop field is already white with flowers by then. The plant is vulnerable to bright light when the sun is on that. Then I use the Harmony cloth at certain irradiance, about 85%," Jan calculates. "Then, if the sun is too harsh, I can close the Obscura another 15%, then you are covered. Because the screens are on top, we also have sufficient ventilation, and the climate remains good."
Jan is outspoken when asked for an interim assessment after a full year: "We are pleased with that cloth. It is an extra tool for us to steer well. Call it a tool to smooth out critical moments. I don't have a comparison regarding energy savings in the winter months, but we use the fabric all year round, which is great!"
