As certified medical marijuana doctors, we often get asked the question “Does marijuana lose its potency?” Over time, cannabinoids degrade and marijuana loses its potency, reducing both the psychoactive and therapeutic effects. Patients have to be diligent about storing their cannabis properly and using it within the recommended time frame. The key is understanding how to properly store it and how quickly to use it.
Why Does Marijuana Lose Its Potency?
Marijuana doesn’t just magically get you high and help you feel less anxious. The effects are the result of compounds called cannabinoids. Cannabis has more than 100 cannabinoids in total, including the well-known THC and CBD along with lesser-known compounds like CBG and CBN.
The cannabinoids are largely contained within the trichomes, those thin and sticky growths that surround the plant. Because the trichomes cover the exterior of your cannabis, your cannabinoids are constantly exposed to air, light, and other environmental factors. This can be bad news, as cannabinoids are extremely vulnerable to heat, oxygen, UV light, and excess moisture.
Even under the best of conditions, your cannabinoids are constantly under attack by external factors. Even if you find a humidity-controlled room and keep your cannabis away from sunlight, CFL bulbs, and LED bulbs (all of which emit UV light), the air you breathe will still present a problem for your stored cannabis. Over time, the cannabinoids degrade, becoming less potent and ultimately breaking down completely.
You can slow down the degradation process with proper storage, but even the best-protected cannabis will lose its potency at some point.
How Long Does Marijuana Stay Potent?
Under normal conditions, your cannabis should maintain most or all of its potency for 6 months to a year. This means that you’re doing your best to keep your cannabis at room temperature in a relatively dark area. If you go above and beyond, such as by investing in a high-quality, temperature-controlled cannabis storage container, you might be able to maintain most of your potency for two years or more.
Research from the University of Mississippi has found that, under normal circumstances:
- Marijuana loses about 16.6% of its THC after one year.
- Marijuana loses about 26.8% of its THC after two years.
- Marijuana loses about 34.5% of its THC after three years.
- Marijuana loses about 41.4% of its THC after four years.
While these numbers might seem low, bear in mind that even a 20% reduction in potency can have a significant impact on the psychoactive and therapeutic effects of marijuana.
Does Marijuana Expire?
Marijuana doesn’t expire in the traditional sense. If you use two-year-old marijuana, you probably won’t get sick from it. You just won’t be able to enjoy it as much. Degraded marijuana won’t get you as high or have the same therapeutic effects. Dehydrated marijuana may burn the back of your throat and leave a bad taste in your mouth.
Old or degraded marijuana shouldn’t inversely impact your health unless mold has grown on the surface. If you spot a fuzzy, powdery, white substance growing on the plant, or if the marijuana smells musty, get rid of it right away. Mold inhalation can cause serious respiratory distress and can even endanger the life of anyone with a mold allergy or compromised immunity. Learn how to spot and avoid mold on medical marijuana.
How to Know if Marijuana Is Fresh
If you purchase marijuana from a licensed dispensary, you’ll often see a date on the packaging. For example, states like Arizona require a Date of Harvest to be posted while states like California require a “Date of Manufacture.” If you don’t see this date, you can ask your budtender for more information about the harvest. You always want to know when your cannabis was harvested.
With this in mind, it’s very important to avoid purchasing marijuana from the street. When you can’t trace the exact origin of your product, you have no way of knowing when it was harvested, if it’s potent, or if it’s even safe.
Eleven states and the District of Columbia have already legalized marijuana for recreational use. In addition, 33 states have an active medical marijuana program. So if you have a qualifying condition, you may be able to obtain medicinal cannabis legally in your state.
Green Health Docs makes it easy to obtain your physician’s recommendation, and if we can’t certify you, you get your money back. Depending on where you live, you may even be able to get your medical marijuana card online. If you’d like to schedule an appointment, give us a call at 1-877-242-0362 or use our website.
How to Keep Your Marijuana Fresh for Longer
In order to maintain the potency of your marijuana for as long as possible, there are four factors you need to take control of: heat, light, moisture, and air.
- Heat: The ideal temperature for marijuana is 70 degrees Fahrenheit (21 degrees Celsius). It’s okay to keep it slightly cooler or warmer, but you don’t want your cannabis to remain excessively cold or hot. If you can’t keep it at 70 degrees exactly, it’s better to go slighter cooler than slightly warmer.
- Light: Always keep your cannabis away from direct sunlight as well as artificial light. Even though conventional light bulbs and sunlight emit only limited UV radiation, it’s still more than enough to negatively impact the cannabinoids and terpenes stored in those trichomes.
- Moisture: Marijuana requires a certain amount of moisture in order to maintain its consistency, but too much moisture can lead to mold growth, microbial contamination, and premature decay. Always keep your cannabis in an environment with no more than 65% relative humidity.
- Air: Obviously you’re not going to keep all traces of oxygen away from your cannabis, but you do want to be careful about environments with excess air circulation. Dispensaries typically store cannabis in airtight containers because they preserve the freshness; you should consider doing the same at home.
For best results, consider storing your cannabis in an airtight jar, and keep the jar in a cool, dark location. You can also invest in a cannabis humidor or other container. This will help you to maintain the maximum potency for much longer.
When Is It Time to Replace Old Cannabis?
As long as your cannabis still has the majority of its potency, it should be safe and enjoyable to consume. However, consider discarding and replacing your marijuana if:
- It has grown mold
- It has dried out to the point where it crumbles between your fingers
- You no longer experience the desired effects
It may cost a bit more money to replace your old cannabis, but the benefits will more than make up the difference.