Does weed go bad?

We’ve all been there- in the middle of spring cleaning when you happen upon some old weed.

Or maybe you’ve run out of fresh cannabis and all that’s left is the remnants of an old stash that has seen better days.

What is one to do? Does weed expire? How long does weed last? And most importantly- can you smoke old weed?

Keep reading to find out!

How long does weed last?

Weed lasts for up to a year or two when it’s stored correctly. It slowly loses strength when in storage for a long time. The main signal that weed is old is how it smells- It’ll smell stale or not at all.

Here’s a table to demonstrate the results of a study about weed storage!

Years in storage

Average THC concentration loss









THC degrades into CBN, and thus you can use the CBN content of old weed to help determine how much THC has been lost.

Weed also loses potency at different rates depending on how it’s stored.


How long does weed last in air tight jars?

Weed lasts two years long in air tight jars but the THC will have lost about 27% of its potency by then. 

Air tight jars are the best way to store weed. Pair them with hydration packs and place the jars in a wooden box for temperature control. And keep it out of the light at all costs!


How long is weed good in a plastic bag?

If you’re just squeezing by with plastic bags, it might be time to up your game. Plastic bags don’t provide any temperature, moisture, or light control. And even worse, plastic can mess up your weed’s trichomes because it has static.

What does bad weed look like?

If you’re wondering how to tell if weed is bad, don’t worry- we’ll walk you through it.

Bad weed can look moldy with a white spiderweb-like substance covering it. It can also look like powder or fuzz.

Moldy weed has a kind of stale, musty smell and tastes weird. Bad weed can also feel spongy or be quick to crumble.

Regardless of how old your weed is, you should always search for mold.

Researchers are beginning to look into the frequency of mold found in cannabis from both dispensaries and cannabis growers.

It’s especially important to check weed for mold if you’re immunocompromised because it can be extra dangerous to smoke moldy weed if your immune system is also weakened.


What to do with old weed?

Old weed is usually safe to use as long as it hasn’t molded. Otherwise it just won’t be as potent. Old dried weed has to have been stored properly in order for it to be safe.

Now let’s assume your old weed was stored well and isn’t moldy. What should you do?

One of the best things to do with old weed is to make edibles because then it doesn’t matter how the weed tastes. Likewise, THC is put to better use in edibles than when smoking it because of the metabollic process it goes through in your body. That way you get the biggest bang for your buck out of the lessened THC content.

Making kief is another great way to use old weed. Grind your old weed with a three level grinder and let the kief collector do its thing!

Kief is a good solution to finding old weed because it separates out the trichomes, aka the most potent part of the weed. You can use the kief in a bowl or joint to add an extra boost!

Can you smoke old weed?

You shouldn’t smoke old weed because it will hit much harsher than new weed and can hurt your throat and lungs.

Not to mention, old weed doesn’t taste or smell very good and wouldn’t be a pleasant experience.

It’s much better to turn old weed into edibles. But if you’re set on smoking your old weed, you should use a bong to lessen the harsh hits.

Scroll to top