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Can Weed Go Bad Or Expire?

17 November 2020
Are those special buds you're storing aging or rather rotting?
17 November 2020
7 min read
Can Weed Go Bad Or Expire?

Read more
  • 1. What happens with marijuana over time?
  • 2. What you should know about using old weed buds
  • 3. How should you store your cannabis?
  • 4. How long do weed buds last?
  • 5. How to tell if your weed buds are old
  • 5. a. How to check for mold
  • 6. Do cannabis concentrates age with time as well?
  • 7. Will freezing your buds prevent aging?
  • 8. In conclusion

Have you ever heard a friend or someone say that they were storing a small bud since who knows for how long? This person claiming that the day when they finally smoke it, this bud will knock them out. 

But do we know if storing cannabis buds for long periods of time is actually possible? Or does cannabis go bad over time? Although marijuana doesn't come with an expiration date, its quality is in fact strongly tied to the storage and curation time.


Weed buds quality and potency changes over time.

Weed buds quality and potency changes over time. Image Source: Elsa Olofsson.

If stored correctly, your weed buds will stay fit during extended periods of time, and might even improve their quality. However, when stored poorly, your cannabis flowers might grow mold and rot. 

1. What Happens With Marijuana Over Time?

It's the inside that matters: inside every weed bud lies a beautiful personality, a combination of plenty of compounds known as cannabinoids. The most common ones you'll probably have heard about already are THC, CBD, and CBN. 

Anyway, each strain of cannabis, or rather each cannabis plant is unique, with their different cannabinoids amounts. More often than not, the compositional structures of marijuana plants will vary a lot depending on their growth process, genetics, and more. 


Cannabis' components mutate over time.

Cannabis' components mutate over time.

Furthermore, this specific chemical structure of each plant continues to grow and change even after the buds have been harvested, put into storage, and perhaps forgotten somewhere hidden for unknown periods of time. This is due to the volatile nature of cannabinoids, which show reactions under the presence of external factors such as light, oxygen, and heat.

In THC's case, for example, the cannabinoid's life starts when the compound THCA, or tetrahydrocannabinolic acid, the precursor of tetrahydrocannabinol is born.

Over time, after going through the decarboxylation process, this non-psychoactive molecule turns into THC, the psychoactive compound that gets users high. THCA turns into THC after the curation process first, and then when hot temperatures are applied to it, getting rid of the carboxyl group. 


When you expose THCA or THC to the oxygen in the atmosphere, or to UV light for a long time period, further changes will take place. If left under these elements for long enough, these compounds will turn into CBNA and CBN, respectively. The longer the buds are left there, the higher the concentration of the new compounds will be. 

While CBN isn't bad for us, it's just different, and sometimes we want to stick to the old-school instead of the different. 

2. What You Should Know About Using Old Weed Buds

If you're looking to get high and you found some weed that wasn't precisely well stored, we're sorry to break it to you but you won't likely get high brother. 

This component we've mentioned before, CBN, or cannabinol, doesn't get you high by itself, so discard the hopes of a trippy time. Nevertheless, CBN is indeed a great compound in the weed family, with potent sedative properties, relaxing muscles, and aiding sleep.

Perhaps that old weed full of CBN you've just found is exactly what you needed to get a good night's sleep


When aging weed for too long, high CBN contents will be found.

When aging weed for too long, high CBN contents will be found.

One thing we must point out about old, forgotten weed buds is that they tend to become too dried out. This, in turn, could result in an extremely harsh feeling as you smoke, which could be unpleasant and uncomfortable, and tends to put people off. 

To counteract this, you could try vaping your aged weed buds to mitigate some of the harshnesses but keep in mind that it will combust at a higher speed so not so much vapor will come out of old buds in comparison to fresh ones. 

3. How Should You Store Your Cannabis?

There are four external factors that can interfere with your weed's potency potential, aroma, and taste:

  • Light;
  • Temperature;
  • Humidity;
  • And oxygen.

Therefore, what you should be looking for to store your weed buds properly is a container that's airtight and a place that's ideally dark and cool, or away from direct sunlight and much heat. 

However, when we say dark and cold we are definitely not suggesting to store your cannabis buds inside a refrigerator. 


4. How Long Do Weed Buds Last?

If you stash your weed properly, using an airtight container, in a dark and cool room, then it could last a lifetime, although it will suffer some alterations.

Usually, dried cannabis stays fit for 6 months to 1 year without suffering any quality or potency affections. If you do exceptionally well, you could extend your marijuana's life for 2 years. After this period of time, your buds could start to lose their aroma, flavor and potency.

According to a study published by the United Nations, marijuana loses about 16 percent of its THC after 1 year, and after this it just keeps dropping. As the information posted in the study states, weed ages in the following ways:


Time Period THC degradation
2 years 26 percent of THC lost.
3 years 34 percent of THC lost.
4 years 41 percent of THC lost.


5. How To Tell If Your Weed Buds Are Old

The most telltale sign that your weed buds are old resides in the smell. Cannabis that is way past its curfew will smell evidently different from al dente buds. Normally, old buds will have a harsh scent or no smell at all. 

Another way to tell how old your buds are is by checking their appearance and touch. If it looks dry and it crumbles, or if it's too spongy when you break it off, that's a clear sign your buds are quite aged. Too much dryness, and contrarily too much moisture are both signs of old weed. 


Check the touch and smell of your aged buds.

Check the touch and smell of your aged buds.

While consuming these old buds shouldn't harm you, do expect to notice some flavor, texture, and potency changes. However, make sure your buds aren't rotten or haven't grown any mold, or else consuming them could potentially make you sick

How To Check For Mold

To check for mold, you must do it very carefully since mold is often quite hard to see unled you check closely. How does mold look like? It's typically like a white powder, sometimes with small fuzzy spots. 

Normally, molded buds will smell musty, slightly like hay. When it comes to flavor, it tends to feel a bit off. 

However, even when your weed isn't extremely old, doing a mold inspection isn't a bad idea either. While buds with mold won't cause anyone any major health problems, it can indeed cause some nausea, vomiting, coughing, and/or diarrhea. 


Check your buds closely for mold.

Check your buds closely for mold.

If you are unsure if your buds are rotten then try checking with a magnifying glass or a led loupe, or ask someone who knows before consuming them.


6. Do Cannabis Concentrates Age With Time As Well?

Just like buds, weed concentrates and other forms of cannabis will reflect the trace of time as well. Concentrates will experience the same chemical changes mentioned above when exposed to the same external factors, light, oxygen, and heat. 


Do weed concentrates last over time?

Do weed concentrates last over time?

Not only the cannabinoids will lose their active power over time but terpenes will start to degrade as well. Your aged concentrates will in turn be high in CBN and low in flavor. 

With concentrates, however, it is possible to keep most of their integrity when they're stored correctly. While the exact rate of their degradation hasn't yet been scientifically tested, you can slow it down as long as you take care not to leave them under UV light and oxygen exposure. 

7. Will Freezing Your Buds Prevent Aging?

Definitely not. Not only freezing your buds won't help to keep them in shape but it could even damage them. 

Sticking your buds into the freezer is a bad idea first because the risks of mold forming are increased due to the moisture, and second, because freezing temperatures can cause the trichomes, the glands responsible for cannabinoids production, to become brittle and break off. 


Don't freeze your weed to keep it from going bad.

Don't freeze your weed to keep it from going bad.

The only form of marijuana you can freeze indeed is cannabutter, which is used to make weed edibles. both cannabutter and edibles can be frozen but only up to 1 month after they've been cooked.

8. In Conclusion

Marijuana is a product of nature and just like most of nature's givings, they have a life cycle to meet. In weed's case, they're meant to be germinated, grown with care, cured with patience, and smoked with joy.

What we mean is, don't be too greedy when it comes to curing, while time is your friend, everything in excess isn't good.

Age your buds just enough so that they reach their maximum potential and then simply enjoy the ride!



  1. "CBN and D9-THC concentration ratio as an indicator of the age of stored marijuana samples" United Nations Office on Drugs and Crime, UNODC, December 1999.