Does Weed Go Bad & How Long Does it Last?

At some point, most weed smokers find themselves asking, how long does weed last?
How Long Does Weed Stay Good For?

It’s a classic scenario: you’re out of bud and in your frantic search for more you discover a long-forgotten baggie of flower somewhere in the back of your closet. You’re excited about your find. But wait: how long does weed last? How long is weed good for? Can you still smoke that old, dried out marijuana? How long does weed stay good, and what happens if you smoke weed that isn’t fresh? This guide has all the information you need.

How Long Does Weed Stay Good: The Basics

Let’s get to the heart of the matter. How long is weed good for? Under ideal storage conditions, cannabis can actually stay relatively fresh for a surprisingly long time.

If it’s been properly harvested, dried, cured, and then stored, you can expect your weed to stay fresh for anywhere from six months to a year.

If you’ve done an exceptionally good job of storing your bud, and you’re a little bit lucky, you may be able to stretch that timeline even further. Possibly to the point of approaching two years.

But for most weed smokers, conditions are less than ideal. In the absence of humidity controlled storage containers, and assuming that your weed will encounter some degree of light and the temperature might be less than perfect, don’t expect to get a full year out of your weed.

So how long does weed last? In general, try to consume all your weed within six months of purchasing it. But, of course, if you’ve invested in high-quality storage equipment, then you can push it out to the year mark.

How Long Is Weed Good For: The Scientific Answer

Now that you have a general idea for how long does weed last, let’s get into the more scientific answer. First, it’s important to understand what actually happens to marijuana as it ages.

Essentially, all the chemicals that make marijuana special break down. Over time, many of the cannabinoids and terpenes found in cannabis slowly break down and lose potency.

As the terpenes break down, your bud loses flavor and scent. As a result, old bud is relatively tasteless and lacks that distinctive, sharp odor that fresh weed is supposed to have. Sometimes, old weed will end up tasting harsh and nasty. Either way, when the terpenes have broken down, your weed won’t taste or smell the way it’s supposed to.

Similarly, and probably more importantly, cannabinoids also break down over time. Old, worn out bud won’t be as potent because a lot of the THC will have broken down and dissipated.

And here’s where we can get very precise with figuring out how long is weed good for. Fortunately, the United Nations Office on Drugs and Crime has looked into things for us.

Their researchers found that, on average, cannabis plant matter loses THC potency at this rate:

  • After one year, weed loses roughly 16% of its THC.
  • Two years in storage results in a loss of 26% of its THC.
  • Weed loses 34% of its THC after three years.
  • After four years in storage, weed loses 41% of its THC.

How Long Does Weed Last: Is Your Weed Bad?

Let’s return to that old bag of weed you found at the back of your closet. How do you know if it’s bad? Basically, you’re looking for a few things:

  • Is it moldy? If your weed was too moist or humid, it may develop mold. Do not smoke moldy weed!
  • Is it dried out? If your bud has crumbled into dust, it’s obviously too old.
  • Does it smell fresh? Old marijuana lacks the crisp scent of fresh weed.
  • Does it break apart? If it’s spongy and doesn’t make any sounds when you pull apart a nug, it might be damp and moldy. If it instantly breaks down into dry dust, it’s too old.

How Long Does Weed Stay Good For?

If you determine that your weed has gone bad, it’s not the end of the world. Technically speaking, you can still smoke it. It just won’t taste very good. And since most of the cannabinoids have probably already broken down you probably won’t get very high.

But smoking old weed won’t kill you or make you sick. The only exception is moldy marijuana. If your flowers have encountered too much moisture they might get moldy.

If you see discolored spots, white fuzzy mold, or if it smells like anything other than cannabis, don’t mess with it. Smoking or otherwise ingesting mold can definitely make you sick or worse, so steer clear.

Now that you know the answer to the question, how long does weed stay good, what should you do to keep it fresh? To preserve your bud for as long as possible, practice proper storage techniques.

Try your best to control temperature and humidity. Keep it away from direct sunlight, and store it in a cool, dry, dark location. With a little bit of care and some basic equipment, you can get the most of your bud.

So, Does Weed Go Bad?

Yes, weed goes bad. In fact, there are a couple different ways it can go bad. On one hand, if your weed sits unused for too long, or you leave it exposed to too much light or open air, it will simply dry out and turn into dusty, crumbly, ineffective flower. On the other hand, if your weed is exposed to too much humidity or other contaminants it could go moldy. And you do not want to inhale mold smoke. Doing so can make you sick.

Beyond the possibility of getting sick from bad weed, keeping your weed fresh will give you a better product and a better cannabis experience. The longer cannabis is exposed to environmental factors such as light and air, the more the cannabinoids and terpenes deteriorate. So if you want weed that will taste and smell great, while getting you super high, take care of your bud the right way.

How to Keep Weed Fresh for Longer

Different cannabis products have slightly different needs if you want to keep them fresh and potent. Here’s a quick breakdown of how to keep different cannabis products fresher for longer:


To keep flower fresh, you need to store it properly. This includes limiting exposure to light and open air, and maintaining a proper humidity level, typically somewhere in the range of 54 percent to 63 percent.

To accomplish all this, store your bud in either a small glass Mason jar or a container designed specifically for marijuana. Keep the lid on tight, don’t open it very often, and keep it in a cool dark place.

And for humidity control, you can either toss in a humidity control pack—check out Boveda, Integra BOOST, or a similar product—or if you want to step up your game to pro level, you can store your weed in a dedicated cannabis humidor such as the Apothecarry, Cannador, or another similar product.


To keep edibles fresh, leave them in their original package and store them in a place that’s away from open air and direct light. Be sure they’re in a cool location, as many types of edibles—especially things like hard candies and gummies—can easily melt.


The best way to keep your concentrates fresh and potent is to store them in small containers designed specifically for dabs. These are typically made out of glass, silicone, or a similar material. Keep the lids on tight and store the containers in a cool, dark place.

Vape Pens

As with any other cannabis product, it’s best to keep your vape pens away from direct light. Because the cannabis oil is already inside an airtight cartridge you don’t really need to worry about humidity or exposure to air. As a final tip, store your vape pen standing upright, as this will keep all the oil at the bottom of the cartridge, ready for immediate use.

(Updated from a previous post.)

    1. I once unknowingly had a $10 bag of weed fall between my dresser and a wall. When I finally saw it while moving furniture, it had become completely white

    2. I have marijuana still good after six months, with no sign of change in effect and potency stored in turkey bags with Boveda included. Checked every two weeks.

      1. I found old weed in airtight metal container, took couple hits & got high, not extremely but still mellowed me out.

  1. Saying that vape carts are air “tight” is false. If carts had their concentrate sealed in an “air tight” cart you would not be able to hit it or take a puff. Carts go bad after 1 years people. Anything over 6 months old is a gamble imho

  2. I don’t smoke much, and I grew way too much pot 3 years ago. I cured it properly and stored it in oven bags (used for roasting turkeys), in 4 separate cardboard boxes. I open each bag a couple times a year to check on it, and take about a month’s worth out from on bag into a jar for smoking. The color has changed, it is no longer green, but a light brownish color. The bags still smell great when I open them, the smoke is not harsh at all, and it still gets me high.

  3. not to brag but
    i risked delivery of SSS Holland seedz to my POB in ’91. Nice.
    Grew indoors for years. The book ‘Tex and Mollie In The Afterlife’ refers to my indoor stuff. Nothing like the passalong bud grew outdoors in ’19.
    Average modern local stuff. However….i put it in ordinary hermetic jars and it lost odor largely, but retained BLAST quality. Enjoy all!

  4. Hey I thought weed smokers were all chill & cool, you know, whatever… you guys sound like fuckin methhead Cincinnati tweaking fags.
    Shut up and smoke your damn weed.

  5. I just smoked some 20 yr old weed. Seriously – really! I got high, but it was slow and minor – but it was ok! It was mummy-weed, dry and crispy! Larro

  6. Used 5 year old cannabis properly stored in glass in dark place not over 70 degrees. Decarbed it 20 mins @ 140 degrees. Simmered about 1/2 cup of this decarbed old cannabis n 2 sticks butter. Cooled and drained. Put in frig in glass jar. Made awesome canna butter. Onset was 90 minutes, the medicial effect lasted 7 hours. Was not “high”, but felt strong body buzz. All aches and pains gone. Mellow. Relaxed. Clear head. Sex was great on it. Extremely hungry. Slept better than have for months. I’d say cannabis is indeed useful even several years old if properly stored.

  7. Yooo at the first comment he def kept repeating the ? Into the answer each paragraph smh dude Def on those flowers but other than that this article was absolutely enabling. Would not suggest this read to anyone

  8. I’ve had bits of weed last or years and still remain potent — without refrigeration but out of direct light. Let’s not forget that ancient weed found in Eurasian tombs was still potent. The hardest part about aging cannabis is not smoking it but as long as it’s kept out of the light and away from moving air, it lasts indefinitely.

  9. My experience differs from what this article says. I grew eleven pot plants on a very long windowsill in 1979. They never flowered, and, when I had to move, I dried the plants in the oven, crumpled up the leaves and little stems, crunched it all up, and put the stuff in two plastic produce bags. Obviously, it wasn’t very potent, but I’m a one-toke high kind of guy, and I got high before going to bed nearly every night for TWENTY YEARS smoking that stash. Its potency never decreased, as far as I could tell.

  10. Hmm. the UN stats appear to indicate that the average THC has a half-life of about 5 years.
    Well, two days ago, I got really stoned on some “Betty Croncker Snackin’ Cake” that spent about 15 years in the bottom of my freezer, at a temp of approx -20C degrees.
    I wuz lookin’ for some spaghetti sauce or chicken-stock that was past its “due-date” and I came across this old bag of goodies. “WOW! Forgot all about them!”. (Well, not really)
    Fifteen years ago I remember makin’ the Betty Croaker cake and modifying it with some MJ I grew in the garden that year. And, when it was baked, I then ate ONE brownie. An hour later I was sitting at the dinner table reading the newspaper, when I started to feel sleeeeepy…
    A couple of hours later I woke up with my head resting on the newspaper, and gradually noticed wetness on the seat.
    OMG- I had pissed my pants! First time in about 60 years! Damn these brownies are dangerous!. So I put ’em in a freezer bag and threw it in the freezer.
    And then forgot about it. Sorta…
    Anyhow, two days ago, I noticed the bag. So I took one piecea cake out, brought it upstairs and nuked it in the microwave for 20 seconds. And then ate it. DELICIOUS!
    Well, I didn’t get sleepy or piss my pants, but the ” ’70s Classic Rock” on the radio was really GROOVY, DUDE! LIKE, WOW! FAR OUT! And I got the Munchies big time!
    So if you really wanna keep some stuff like this a long time, keep in a VERY COLD freezer.
    Hmmm… think I’ll rescue another piece from the freezer tonight… Before my now-adult kids read this.

  11. Just found a hidden compartment in a grinder I got off a friend four years ago! The best part was the huge nug I found hidden in it! Currently trying it out- but harsh to smoke but feels pretty good!

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