The results of a controlled horticulture lighting study conducted by the Center for Lighting Enabled Systems and Applications (LESA) at Rensselaer Polytechnic Institute have been released, citing Lumileds LEDs as the top performer.

The study, utilizing a variety of commercial LEDs, compared the effectiveness of different LEDs on the growth of red lettuce Rouxai. The best combined yield and antioxidant concentrations in the lettuce was observed using Luxeon SunPlus Series LEDs.

“Comparing the growth results using different combinations of LEDs shows that the spectra that performed best for yield (fresh weight), anthocyanin and chlorophyll concentrations were the Luxeon SunPlus Lime + Purple and Green + Purple LEDs from Lumileds,” said Tessa Pocock at LESA. “Green light is necessary for crop growth and the specific wavelengths within the green region matter.”

This work is also part of the Greenhouse Lighting and Systems Engineering Consortium operated by LESA and Cornell University and funded by the New York State Energy Research and Development Authority to examine the most effective way to add green light to horticultural fixtures.

“Growers today are experimenting with various LEDs to arrive at the best color combinations for their crops. The LESA study indicates that such experimentation is paying off because a common, nutrient-rich crop can be produced with excellent yield,” said Jennifer Holland, product line director of the Luxeon SunPlus Series. The study demonstrated that a light spectrum like the combination of lime and purple devices, which contain a certain ratio of royal blue, green, deep red and far red components, is beneficial to growth optimization.

LESA is funded by the U.S. National Science Foundation.