US: Study examines the differences between LED Lighting and HPS

Abstrax has released a first-of-its-kind white paper analyzing how HPS and LED lighting affect a wide range of secondary metabolites in cannabis, including compounds like cannasulfurs that have never been studied in this context. The study was conducted in partnership with Josh Del Rosso, also known as Josh D – the legendary grower who introduced OG Kush to California and helped make it a staple of West Coast cannabis. A pioneer of hydroponic cultivation in Los Angeles, Josh D helped usher in a new era of urban cannabis growing just as indoor lights, Rockwool, and liquid nutrients began to shape the game. The research, titled Which Light is Right: The HPS vs. LED Debate in Cannabis Cultivation, compared how his iconic OG Kush performed under both High Pressure Sodium (HPS) and Light Emitting Diode (LED) systems. The results challenge common assumptions and may surprise even the most seasoned cultivators.

The debate between HPS and LED lighting has divided the cultivation community for years, with questions around their impact on cannabinoid potency, morphology (bud shape and structure), and terpene expression still unresolved. In this study, Abstrax and Josh D put those questions to the test using a side-by-side grow of his award winning OG Kush, cultivated under tightly controlled conditions. The plants all shared the same genetics, nutrients, and environment, with lighting as the only variable.

"This wasn't theoretical," said Kevin Koby, Chief Executive Officer at Abstrax. "This was one of the most iconic cultivars in cannabis history, grown by the breeder who made it famous, under two modern lighting systems. The results show that you can maintain quality while gaining flexibility and that you can carefully tune bag appeal to match your market."

The authors note that while striking morphological differences were observed in the OG variety grown, other varieties would likewise be of interest to study how light may affect this critical product characteristic. For instance, varieties that tend to have a looser bud structure naturally may benefit from different light spectrum exposure if a tighter morphology is desired.

As energy costs rise and cultivators look for every edge available, understanding how lighting affects not just plant growth but bag appeal, flavor intensity, and consumer perception has never been more critical. This study offers actionable insights for growers looking to transition to LED, improve efficiency, or fine-tune morphology for product differentiation without sacrificing the chemical fingerprint that defines high-quality flower.

The paper is now available at the link here and includes full experimental methods, chemical analysis, and side-by-side flower comparisons.