Does Weed Go Bad?

marijuana flower mass storage jars

If you've ever come across some questionable cannabis buds, you've probably been tempted to smoke them regardless. Cannabis flower nugs can lose their potency and aroma if stored improperly or for too long. Dried cannabis doesn't get swarmed upon by microorganisms like food products do, but it can still dry out and produce a harsh-tasting smoke. Weed usually doesn't actually go bad; it just goes through multiple chemical reactions. Here's Leafbuyer's guide on weed's shelf-life and how you can extend it. 

How Cannabis Ages

cannabis flower mini containers

During the cannabis plant's flowering cycle, it produces a cannabinoid acid known as cannabigerolic acid (CBGA). CBGA is a vital compound that is used to form other major cannabinoids such as cannabidiolic acid (CBDA), tetrahydrocannabinolic acid (THCA), or cannabichromenic acid (CBCA). Decarboxylation, or the act of heating, converts inactive compounds in trichomes into primary cannabinoids such as THC, CBD, and CBG. 

When you buy cannabis buds from a licensed retailer, you'll receive nugs with some primary cannabinoids, but mainly inactive cannabinoid acids. Cannabinoids and terpenes undergo chemical reactions due to heat, light, and moisture exposure. If cannabis buds were to be left indefinitely in a mason jar, the THCA would convert to THC and eventually degrade into cannabinol (CBN) with exposure to light and high temperatures. 

Factors such as temperature, humidity, UV light, and oxygen can affect marijuana bud degradation. Over time, your cannabis nugs will lose their potent cannabinoids and aromatic terpenes.  A study released by the United Nations Office on Drugs and Crime measured the concentration of THC of buds stored at room temperature over a four-year period. On average, cannabis plant material lost THC concentration at the following rates: 

  • 16% THC loss after one year
  • 26% THC loss after two years
  • 34% THC loss after three years
  • 41% THC loss after four years

Does Weed Go Bad?

old moldy marijuana flower

Weed doesn't necessarily go bad in the sense that it may cause you physical harm, but your flower nugs may suffer from a mold infestation, which can be harmful to your health. Mold can grow on your cannabis if your storage is too humid or moist. Moldy buds can exhibit a fuzz or dark spots within its leaves. Mold gives off a musty odor reminiscent of urine or sweat. If your weed smells unpleasant, play it safe and toss it. 

If, however, you have a few grams of old weed that look a bit dry and brown, the worse that may happen if you smoke it is a bad headache and coughing fits. Crumbly, brittle, and odorless weed may be harsh to smoke. Furthermore, it may not have a decent amount of cannabinoids, which makes the unpleasant smoke not worth it. 

How Long Does Weed Last?

The best storage practices can keep cannabis relatively potent for up to a year. More than likely, most cannabis consumers don't use humidity packs or carefully monitor relative humidity. After regular light exposure and temperature variances, weed can last about six months after purchase. Some users consume their stash well before the six-month mark, but any buds stored longer than that won't taste as good and won't be as potent. 

What About Other Cannabis Products?

Cannabis labels on products such as edibles can clearly tell you when the product should be used by. Everything from cannabis edibles to tinctures to concentrates go through the same degradation process as cannabis flower. Similarly, cannabinoid content in these products are affected by exposure to light, heat, and moisture.  

Edibles with ingredients such as milk and eggs can spoil quickly, rendering your edibles useless. Many users keep their edibles refrigerated or frozen to extend their shelf life. Edibles may be good up to a week after purchase, depending on their ingredients. 

Concentrate shelf life depends on a variety of factors including the quality of the material and the storage practices. For example, shatter can "sugar-up," a process known as nucleation. Nucleation occurs when certain compounds separate in the shatter from the cannabinoids. Sugary shatter doesn't go bad, but it won't contain its original chemical profile and aroma. 

How to Best Store Weed

dark weed storing container jars

Now that you know that weed can lose its potency and aroma, you can take proactive steps to store your buds or other cannabis products in a cool, dry, and dark place.

One of the most important components of cannabis storage is an airtight container. Many cannabis users use a clear mason jar. Some nug jars even protect your weed from harmful UV rays. Airtight containers don't just control the smell, but also slow down cannabis degradation. 

If you want to go above and beyond in your storage practices, invest in humidity packs that remove excess moisture and release it when needed. Some humidity packs are especially designed to maintain an optimal relative humidity of 62ºF. For larger and extended storing options, consider vacuum sealing to remove all air from a package. If you're taking the vacuum sealing route, make sure to avoid using a material that uses bisphenol-A. 


Your weed deserves the best storage available for what you're paying. If you're looking to store different kinds of marijuana products, consider these helpful tips and tricks. Now that you're armed with knowledge on weed's shelf-life, you will be better equipped to determine if old weed is worth smoking and better equipped for buying your favorite cannabis strains and keeping them fresh, potent, and enjoyable for longer!