It is well documented that the light is the main factor or one of the factors influencing plant growth and development. The role of light spectral quality in meeting the specific needs during a plant’s developmental stages (germination, vegetative and flowering) has not been well defined and investigated. The objective of this study was to investigate the impact of light spectral quality on the growth and yield of cannabis plants during different developmental stages. Cannabis plants were grown in a controlled environment with distinct light spectral quality treatments applied at different growth stages. The plants were monitored for morphological responses and cannabinoid content. This study evaluated the hypothesis that, just like the dietary needs of human beings change with age, plants' nutritional and lighting requirements change with their growth stage. Plants' metabolic responses can be triggered and maximized by giving them the right light spectrum and intensity as the plant undergoes the development phases of its cycle. The results showed that the dynamic spectrum lighting led to a 33 % increase in yield and significant improvement in cannabinoid content. These findings challenge the conventional belief that a fixed full-spectrum white light is optimal for plant growth and development. Furthermore, it is hypothesized that plant development stages can be divided into more than the existing three conventional stages. This optimization resulted in the highest yield and energy savings under the dynamic spectrum. These novel findings will have important implications in motivating plant scientists to go beyond the conventional norm and could pave the way for a paradigm shift towards dynamic spectrum lighting, thus taking a leapfrog jump in shaping the future of horticulture lighting.