Effects of red, blue and white light on the growth and development of Cannabis Sativa L.
A team in the Czech Republic published a study in November of 2017, which investigated the effect of red, blue and white light on the morphological and photosynthetic qualities of Cannabis sativa L. The overall study did find that white light (WL) emitting full spectrum of light affects plant growth and development better than Blue Red (BR) light. Namely, the plants grown under WL had an average leaf area of 100.03 cm (squared) compared to plants grown in BR light with an average leaf area of 79.54 cm(squared) . The WL treatment showed an increased plant height compared to BR treatment.
Before deciding on a new LED light, I often ask clients to trial, and to select the most effective spectrum for their strains. Often Blue Red LEDs are tempting to go with, but testing, and understanding the final outcome of your plants using specific spectrums can pay off the price differential, as LED manufacturers, such as Valoya out of Finland, are working intensely to ensure your horticultural team is working with the best possible spectrum available on the market today.
I'll be continuing to pursue studies and data on this subject and analyze the payback of various LED strategies