Does Weed Go Bad? How to Store Cannabis

Does weed go bad?

Weed doesn’t expire, or go “bad”, but it does lose potency. Over time, the THC in weed breaks down into cannabinol (CBN), which is not psychoactive. While CBN is safe and may even have certain health benefits, aged weed will get you less high.

Old weed will also dry out, become more brittle, and change in aroma.

So how long does weed last?

When weed is stored in a dry, airtight, and dark place (we’ll discuss this more later), it can last quite a while. According to a study done by the Research Institute of Pharmaceutical Sciences, THC in weed degrades at the following rate:

16 percent THC lost after 1 years
26 percent THC lost after 2 years
34 percent THC lost after 3 years
41 percent THC lost after 4 years

Weed lasts quite a while when stored properly. However, if you plan to preserve your weed it's important to make sure you are keeping it in the right environment.

Can mold grow on weed?

Yes, mold can grow on weed if stored improperly. Although it is unlikely to cause major health problems, it can cause vomiting, coughing, nausea, or an upset stomach.

If your weed is old, or if you’re worried about how it has been stored, then it’s best to inspect your weed for signs of mold before consuming. The signs are often very subtle, but look for unusual signs of white powder, fuzz, or spots. Additionally, moldy weed may develop a stale smell like hay.

How should weed be stored?

There are 4 major factors when considering weed storage: light, temperature, humidity, and oxygen.

Light: Weed should be stored in a dark place. UV exposure can cause weed to degrade and grow brittle.
Temperature: Store your weed at temperatures between 40 and 77F. Too much heat can lead to mold, and cold temperatures can actually damage the precious trichomes which hold much of the THC and CBD in the flower.
Humidity: It's best to store your weed at a relative humidity of 59-63 percent. This is the magic window which prevents mold growth and also doesn't dry out your weed. If you want to go the extra mile, you can buy small humidity packs to help control the moisture in your container.
Oxygen: Oxygen dries out and degrades your weed over time. Use an airtight container suited for the amount of weed you want to store. Avoid using a container with lots of excess space as it will increase the oxygen in contact with the weed.

Ultimately, weed should be stored in a cool, dark, and airtight container. If you don't have a solution yet, we highly recommend you check out Cubbi, which creates airtight, smell proof containers specifically designed for cannabis storage.