How to Know if Weed is Expired
Is it your lucky day!? Did you finally find a hidden stash that you determined was gone forever? A pre-roll wedged between couch cushions? A half an edible you were saving for later… but the need for it ‘later’ never came? Even a vape cartridge that’s been sitting at the bottom of your purse or gym bag? Whether it’s been a few months or you have no idea how long it’s been hiding, of course you’re going to wonder, “Is this weed any good? Can I still get high?” Let’s get to the bottom of how to know if weed is expired.

Cannabis Shelf Life
With most things that we buy fresh, there comes a “Best Used By” date. Not so much when it comes to cannabis. This is mainly due to cannabis laws and regulations, and the fact that every cannabis strain has its own attitude when it comes to staying fresh. The one main factor that influences the shelf-life of your cannabis comes down to how you store it. We’ll go over proper storage, but first let’s look at the standard expirations for different cannabis products and how to tell if it has gone bad.
Expiration by Cannabis Product Type
The standard for fresh cannabis flower
If you are keeping your fresh cannabis flower stored properly, you won’t have to second-guess if it’s expired for the first year. The standard is from 6 to 12 months, after that, you are just looking at a lot of THC loss. Now, if you have already thrown your bud into a grinder, you’re looking at 2 weeks, tops.
There are studies that really get down to the nitty gritty on THC loss during the shelf life of fresh cannabis flower. One study found that there is a decrease in THC levels by about 16% within the first year. Then a 26% decline in THC by the second year. The third year there is 34% less THC, and by year four, the potency of THC diminishes by about 41%.
Concentrates
You can expect your dabs and weed vape pens to stay fresh for about 2 years. Solvent-based concentrates actually preserve THC, making it harder to degrade or go bad due to the solvent (like butane or CO2) that is used during the extraction process. When it comes to solventless concentrates, like rosin and hash, the shelf-life shouldn’t push past a year and a half.
A little side note, with RSO (Rick Simpson Oil) you might notice a slight darkening of color and a change in texture. These changes do not necessarily indicate that the RSO has expired or is unsafe to consume.
CBD Tinctures
Just like with concentrates, you should expect your CBD tincture to stay fresh for around 2 years. The great thing about this is hopefully you are finishing the bottle way before the 2 year mark.
Cannabis Edibles
A lot like your fresh cannabis that is ground up, your edibles are going to lose their freshness very quickly. Baked goods and chocolates use fats and oils that will go bad within a couple of weeks. Most of these actually come with a label on them suggesting a “Best Used By” date. Gummies and hard candy on the other hand, have a lower moisture content than baked goods, so you can expect them to stay fresh for several months.
Cannabis-infused Cosmetics
Cannabis topicals like creams, balms, lotions, gels, etc., have a very promising shelf life. When it comes to any cosmetic product, industry standards are a maximum of 2 years. The waxes, oils, and other ingredients used in these products can break-down and possibly irritate your skin.

Signs of Expired Cannabis
The very first thing that you can’t really tell is happening is the loss of potency. Of course, this is noticeable once you light up your usual smoking amount and realize you aren’t feeling the same effects as strongly as usual. But, this is the major downfall of aging cannabis flower.
How to Tell if Cannabis Flowers Are Bad
There are some pretty clear signs that your bud is better off being laid to rest. Smell, feel, look, and flavor, are your main concerns. Having a musty smell or no smell at all, yeah, that means all of the juicy flavonoids and terpenes are worthless. Any sign of discoloration, like yellow or brown, is a clear indication that your cannabis flower is RIP. Lastly, for those of you who are beyond curious and would rather just light it up, if the hit is particularly harsh, and the flavor is bland, you’re smoking expired weed.

How to Check for Weed Mold
You cannot mess around with moldy weed! It’s toxic, gross, and just downright bad. So, how do you know if there is mold on your weed? A major sign is if there are any water droplets (precipitation) on the inside of the container your flower is in. You’ll want to check for fuzzy white or grayish patches, black spots, or powdery substances. Mold spores that haven’t fully taken over your stash can look a lot like crystally trichomes. Give your bud a good pinch and smell test. If anything feels off, like a rancid, dull aroma, or slimy and spongy to the touch, it’s highly likely that there is mold forming.
Cannabis Freshness Guidelines
For the most part, even though each legal state has its own guidelines for cannabis, there is a pretty standard set of rules and regulations that determines fresh cannabis. In 2018, the Marijuana Regulatory Agency (MRA) of Michigan placed protocols for testing. The tests check for several contaminants, like mycotoxins, levels or moisture, presence of pesticides, leftover solvents or any heavy metals. Aside from these tests, the cannabis flower gets tested for its terpene and cannabinoid profile, and the levels of THC and CBD.

Storage and Preservation
Tips for Storing Cannabis
Your main goal in keeping your weed healthy is to keep sunlight, moisture, and air flow far away from your stash. This means that you need to store your cannabis in something that fits the following.
- Container: Glass jars with airtight seals. Opaque containers like ceramic jars and tin cans. Or Mylar bags that block out moisture and light.
- Environment: Keep your cannabis container in a place that has a temperature between 55 and 70 degrees. Also make sure the humidity stays between 55% and 62%. There is no science experiment that you need to perform, somewhere like a backpack, closet, drawer, pretty much anywhere that you personally feel comfortable in the environment.
Can You Freeze Cannabis Products?
This is an iffy option with good and bad effects. The only reason for freezing your cannabis products is if you are planning on storing the cannabis for an extended time. Storing your cannabis in the freezer can help slow down the degradation process and preserve its potency. But… freezing your weed can damage the delicate trichomes as they become brittle and break off the flower easily.
You shouldn’t freeze your cannabis products if you are constantly taking it out, opening the container, and putting it back. Frequent temperature fluctuations cause moisture and welcome mold and microbial contaminants.