Examining the effects of the light spectrum on terpene levels

Cannabis is renowned not only for its cannabinoids like THC and CBD but also for its terpenes—organic compounds responsible for its unique aromas, flavors, and therapeutic effects. Terpenes like limonene, myrcene, pinene, and linalool contribute to the plant's sensory experience and potential medicinal benefits. While many factors influence terpene production, the light spectrum during cultivation plays a critical role in determining terpene profiles.

What are terpenes?
Terpenes are aromatic hydrocarbons produced in the glandular trichomes of cannabis flowers. They serve ecological functions, such as attracting pollinators or repelling predators. In cannabis cultivation, terpenes enhance the plant's market value and therapeutic potential. Specific terpene profiles are linked to effects like relaxation, focus, or pain relief, making them a key focus for both recreational and medical users.

The role of light in cannabis growth
Light is essential for photosynthesis, the process by which cannabis converts light energy into chemical energy. However, the quality of light—defined by its spectrum—affects more than just growth and yield. The spectrum also influences secondary metabolite production, including terpenes.

Light is typically characterized by its wavelength, measured in nanometers (nm). Different parts of the light spectrum have distinct effects on cannabis plants.

Blue Light (400–500 nm): Stimulates vegetative growth and can enhance terpene production by promoting the biosynthesis of essential oils.

Red Light (600–700 nm): Supports flowering and bud development but may not directly influence terpenes.

Ultraviolet (UV) Light (100–400 nm): UV light triggers stress responses in cannabis plants, which can lead to increased terpene production as a defense mechanism.

Far-red Light (700–800 nm): Affects internode length and flowering. Some far-red light can be beneficial in terms of yield production, but too much of it can reduce secondary metabolite production.

Balanced Spectrum for Optimal Results: While UV and blue light are beneficial for terpenes, an unbalanced spectrum can stress plants excessively, reducing overall health and yield. Broad spectrum LED lights that simulate sunlight offer a balance of all wavelengths of light to ensure robust growth and optimal terpene development.

Valoya's solution for growers
Based on extensive and continuous research with growers, universities, and other research institutes, Valoya has found that in addition to increased yields and cannabinoid concentrations, its Solray385 spectrum can enhance terpene production as well.

A trial with 40 different chemovars conducted on Solray385 in North America showed a significant increase in both THC and terpene concentrations in comparison to a competitor LED focused in cannabis production:

A comparative trial between Valoya LED Solray385 vs. HPS Hybrid setup with 24 different cannabis chemovars in North America showed similar results:

A third trial in North America showed a 9,6 % increase in average of 19 analyzed terpene profiles, in addition to higher total THC concentration:

Conclusion
The light spectrum is a powerful tool in cannabis cultivation, influencing not only growth but also the quality of the final product. By understanding how specific wavelengths impact terpene production, growers can choose the optimal lighting to produce aromatic, flavorful, and therapeutically potent cannabis.