05 February 2019
Larger blooms, more lush clean green leaves and fewer thorns. According to Signify (formerly trading under the Philips brand name) cut roses Red Naomi! and Avalanche+ thrive well under Philips GreenPower LED toplighting whose light recipe has been adjusted.
One year after the introduction of LED lights with the new rose spectrum, it appears that the roses react well to the new light spectrum, Signify have stated.
The combination of LEDs and climate control based on the principles of the Het Nieuwe Telen (HNT) project brings top quality and sustainability closer. HNT loosely translates as the New Way of Growing or Next Generation Growing with a strong focus on environmental conditions such as temperature and humidity.
The first results of research carried out at the Delphy Improvement Centre in Bleiswijk, Netherlands, reveal that Signify’s new light recipe developed in collaboration with Wageningen University & Research (WUR) has a particularly positive effect on leaf quality, number of thorns and bud size.
“We are very happy with the results we are achieving with the new rose spectrum,” says Leontiene van Genuchten, plant specialist at Signify. “Where we saw earlier that crops did not perform well, the quality remained good this winter. We see the same result at practice companies where we test the new rose spectrum.”
The Red Naomi! rose crop endured a warm and testing summer. Moreover, part of the crop was uprooted in April and replaced by Avalanche+, which meant that testers had to rebalance the crops in an area where young and older crops stand side by side. “The number of branches per square meter was very high last summer, but the branch quality was insufficient,” says researcher Arie de Gelder of Wageningen University & Research. ”
The young Avalanche+ crop looks good. The researchers see a healthy and vigorous crop, with thick branches. The leaves look a bit dark. “We must maintain a moderate climate for both varieties. We could actually grow Avalanche+ in somewhat warmer conditions, but this would be at the expense of Red Naomi!,” says De Gelder. “We see that Avalanche+ is responding well to the new light spectrum and that is a good thing.”
The new generation Philips GreenPower LED toplighting is equipped with the latest lighting recipe specially developed for the rose crop. A small amount of white light has been added to this spectrum, so that the greenhouse employees can better assess the crop when harvesting or scouting. The new module has an output of 500 to 600 µmol/m²/s each at very high efficiency of up to 3.0 µmol/J.