Combination of red and UV-A light enhances hemp (Cannabis sativa L.) inflorescence yield and cannabinoid content

Abstract Light spectrum plays a crucial role in regulating the growth of hemp (Cannabis sativa L.) plants and the biosynthesis of secondary metabolites. Several studies have demonstrated that additional red-light exposure increases biomass accumulation, while supplementary UV-A light stimulates cannabinoid synthesis. Nevertheless, the potential of stage-specific supplementation of red and UV-A light remains underexplored in its capacity to optimize cannabinoid yield in indoor hemp cultivation. In the present study, the effect of red light in combination with UV-A light on