Ultraviolet light (UV) is a spectrum of light that is invisible to us but is visible to certain insects and organisms. UV light can be broken down into three subtypes: UVA, UVB and UVC, which vary in terms of wavelength. UVC is absorbed by the earth’s atmosphere, while UVA and UVB affect cellular structure, notably causing sunburns and wrinkles on human skin tissue. Why are we concerned about UV light? Because when storing cannabis, UVB degrades THC, which ultimately affects potency. In a world where an ounce of cannabis costs +$200, why not do everything possible to ensure your bud is safe?
UV is not all evil, though, so it’s important to break this into two subjects: UVB in relation to growing cannabis, and UVB in relation to storing cannabis. The potency of high quality marijuana increases in direct ratio to the amount of UVB light it receives during cultivation. Some growers tout that by adding UVB radiation (either through tanning lamps or direct sunlight), they saw increased THC potency by 3-5%. Cannabis storage and UVB is a different story. We commonly cite a rather outdated study, but considering that no one else has taken up this subject, we’ll cite it again; The Stability of cannabis and its preparations on storage (1976) by J.W. Fairbairn, J.A. Liebmann and M.G. Rowan discovered that storing cannabis in amber bottles with limited exposure to light still lost 7% THC per year.
We’ve turned to Miron glass jars when it comes to glass storage because these jars block 99% of UVB, whereas clear glass jars like mason jars let in nearly all UV light. So in summary, adding UVB light to your garden will enhance your cannabis naturally and increase THC levels, but exposing UVB to cannabis after it has been harvested during storage will degrade THC. Clear as mud? We hope so!