As soon as a cannabis plant has been harvested, it begins to degrade. Not only is the plant itself no longer alive and receiving nutrients from the root ball it was once attached to, the cannabinoid biosynthetic pathways have been disrupted as well. In this process, cannabinoids and terpenes synthesize into other compounds, subsequently altering their psychoactive properties. For example, the temperature has the ability to cause THCA to decarboxylate and become THC (which is highly psychoactive), but heat and light can cause THC to degrade toCBD and CBN over time as well.
Once a cannabis plant has been harvested, dried, and cured, its optimal freshness zone becomes a finite window that can be extended only by carefully controlling various elements that include not only temperature and relative humidity, but also UV exposure and ambient oxygen levels.
Where temperature and humidity are both highly influential to cannabis degradation, high exposure to UV light and oxygen can perhaps cause the highest rates of degradation in the shortest time frame. UV rays can break down organic matter at a rapid rate, causing cannabinoid degradation and loss to occur. This process can only be slowed by limiting light exposure to cured flowers.
Elevated exposure to oxygen can also cause rapid cannabinoid degradation. THC, when left in highly oxidizing environments, will convert more rapidly to CBN, which is why it’s important to control both oxygen levels and RH when curing cannabis buds.
Controlling these variables and maintaining their proper levels can significantly prolong the shelf life of your cannabis flowers by limiting exposure to the processes that influence the degradation of not only the floral clusters themselves but the cannabinoids and terpenoids contained within them.
Although cannabinoid degradation is an inevitability and your cannabis will eventually expire, maintaining a highly controlled environment is the best way to combat the natural processes that will render your stash undesirable, leaving you with fresh flowers for longer than you may have previously anticipated.