The Impact of Light Intensity and Spectrum-Tuning on Cannabis Yields
14 Pages Posted: 15 Jan 2019
Date Written: January 4, 2019
This study investigates the impact of light intensity on cannabis yields. We also look for evidence that specialty grow lights affect that relationship when compared to general application, broad-spectrum (white) lights. Finally, we discuss the return on investment associated with using more electricity in order to increase light intensity and yields. The experiment includes hundreds of plants. As far as we know, this research represents the first university study of the relationship between light and cannabis yields, and the results challenge industry conventions. We find that yields increase linearly with light intensity up to at least 1500 μmols/ m2· s, which is over twice the intensity that is most commonly used by cannabis growers. We also find no evidence that spectrum variations across our sample of specialty horticulture lights significantly affect yields versus general purpose broad-spectrum lights. Finally, the value of the gain in yields from increasing light intensity far exceeds the cost of additional electricity for all the intensity ranges that we considered.
Keywords: Cannabis, LED lighting, HPS, Yields
JEL Classification: Q
Suggested Citation: Suggested Citation