How Long Does Weed Potency Last?

July 20, 2020

Have you ever found a long-forgotten about container of weed stored in the back of a drawer? It can be a pleasant surprise until you see the condition of the old stash – maybe it’s a bit stiff, dried out or just plain mummified from being there so long. Faced with such a situation, there’s only one natural response: does weed potency actually go down or can I smoke or use this to make edibles?

Well the good news is that weed never goes “bad” in the sense that it becomes unsafe to use after getting too old, provided you haven’t left it in a humid environment where it will develop mold or mildew. However, weed can go “stale” or lose its freshness if forgotten about too long, and nobody likes stale weed if they can help it. So how long does it usually take for weed to lose its freshness?

Conditions that Determine Weed Freshness

The first thing to understand is the conditions that help weed to stay fresh. Depending on the conditions your long-lost weed has been stored in, it may still be good after several months, or it may have long-since crumbled into a fine dust. The good news is that any weed that has been professionally harvested, dried, cured and stored will stay fresh for longer – usually anywhere between 6 months to a year.

That means if you are getting your weed from a dispensary, you are already getting weed that will stay fresh for as long as possible. However, apart from the harvesting, curing and storage of the weed, there are also a few factors that can influence freshness after you take your weed home.


As previously mentioned, controlling the humidity your cannabis is stored in will be one of the most important factors for keeping your weed fresh and safe for consumption. Weed kept in environments that are too humid can develop rot or mold, and make you very, very sick if you ingest it.

Finding a way to not only control humidity, but find the right balance can be a bit tricky, but generally you will want to keep your cannabis flower between 59% and 63% humidity levels. Storing at these levels can keep your bud fresh for longer, helping to preserve the aroma, consistency and taste of your weed. Mold typically develops at humidity levels above 65%, so it is important to keep below that threshold, although storing at too-low humidity will accelerate your weed drying out.


Light is also an important factor to consider when storing weed, as UV rays can break down the chemical components of cannabis like THC and CBD. Although humidity is the most important factor from a safety perspective, light is the most impactful factor on how long weed will stay potent. Under the right lighting conditions, cannabinoids can stay intact for as long as two years.


Related to lighting, temperature is another important factor in how you store your weed. You generally want to store your weed in a cool, dry environment. However, you should not mistake “cool” for “cold” or “freezing” – never store your weed in a refrigerator or a freezer. Doing so will expose it to fluctuations in temperature as you open and close the fridge/freezer, accelerate mold or mildew in the fridge, and break down the trichomes in freezers.

What Makes Weed Seem Stale

As weed ages, the chemical components of the cannabis will slowly break down over time, the same as any other substance. The main psychoactive component of weed (i.e., the component responsible for giving you a “high”) is THC. Over time, weed will slowly lose its THC, and therefore its potency.

  • After one year, weed loses ~16% of its THC
  • After two years, weed loses ~26% of its THC
  • After three years, weed loses ~34% of its THC
  • After four years, weed loses ~41% of its THC

Effects of Stale Weed

So, although weed may slowly lose some of its potency over long periods of time, it will never “expire” the same way groceries do. But that doesn’t mean that you should let your weed go stale. Besides the biggest detriment of losing potency over time, weed will also slowly lose its aroma, texture and flavor over time.

In the most extreme cases, you will be left with nothing more than a stash of impotent, crumbly dust that isn’t usable for anything.

Ideal Conditions to Keep Weed Fresh For a Long Time

So, with all that information at our disposal – how do you keep weed fresh for a long time? The most important factor is going to be how and where you store your weed. You will want to avoid storing it in plastic baggies or overly large containers, and ensure that the weed and container you are using are not exposed to light or heat.

The best solution for storage of up to six months is to store your weed in an air-tight glass jar with a seal to keep out humidity – mason jars are a great option provided they are not overly large for the amount of weed you are storing. If you know you will want to store your weed for longer than six months, you will need to consider more involved storage options, like a dark, cool, dry root cellar.

Visit Pure Oasis for Your Next Resupply

Have any more questions about keeping weed fresh? Pure Oasis is a boutique shop offering a user-friendly experience, with knowledgeable staff here to guide you with information and advice on all of our high-quality products.

Whether you are a first time cannabis user looking to explore the benefits of marijuana use or a long-time connoisseur, Pure Oasis is focused on your needs and making your cannabis shopping process smooth, efficient and enjoyable. Our coffee-shop style dispensary is designed to make shopping a breeze and our knowledgeable staff is here ready to guide you through our many choices.

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