This trial yielded some surprising results with one light recipe in particular. The LUE (Light Use Efficiency) was shown to be higher under the hybrid installation, meaning chrysanthemums make very efficient use of light from LEDs. Two different LED spectra were tested and there were big differences in how they influenced the plants. The chrysanthemum stems were much heavier when grown under the best light recipe. These results actually prove that added value of LED lighting, which was found in the previous smaller trials, does exist.
Commercial growers have been waiting for a large scale confirmation of an effective LED light recipe, which is exactly what we achieved at Arcadia. With this chrysanthemum light recipe, growers can either use a hybrid installation to grow heavier stems or put more plants in a square meter to increase yields.
This trial was based on LED and HPS lighting, so the next step for Philips is to search for a 100% LED light recipe for chrysanthemums. We have seen promising results with chrysanthemums grown in a small trial of 100 square meters with 100% LED at the HAS (University of Applied Sciences) in ‘s-Hertogenbosch, The Netherlands. We set up this trial with the support of the Delphy Improvement Center and some commercial chrysanthemum growers. The results with LEDs alone have already produced very nice branches on the plants and research will continue.
When you add up the growing body of evidence, the business case for growing chrysanthemums under LED plant lights is strong. In fact, based on these results we are looking at new LED installations for a number of chrysanthemum growers. The first commercial project with Philips LED lighting was sold earlier this year to Linflowers in Brakel, The Netherlands. They chose to partner with Philips Lighting to add 48 µmol/m²/s LED growing lights to their existing HPS installation for an area covering 37,152 square meters. These steps forward confirm that the close collaboration between growers, researchers and Philips is the right formula for finding the right light recipe.