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How Long Does Weed Stay Good without Losing Potency

How Long Does Weed Stay Good

Cannabis, a plant revered for both recreational and medicinal uses, requires careful handling to maintain its quality. After storing it in airtight containers, how long does weed stay good? If the cannabis goes bad, are there any signs you should care? In this post, we will focus on the lifespan of dried cannabis, guiding you to finish the weed without missing its peak potency. 

Table of Contents

Does Weed Have An Expiry

Unlike homegrown veggies or fruits, cannabis does not have a specific Best Before date. However, while it doesn't "expire" in the traditional sense like perishable food items, it decays in other noticeable ways:

  • Potency Loss: The primary psychoactive component of cannabis, THC (tetrahydrocannabinol), degrades over time, especially when exposed to light, heat, and air. We’ll go deeper into this potency loss in the next section. 
  • Quality Deterioration: Over time, the aromatic compounds in cannabis, known as terpenes, can also degrade. This affects the flavor and aroma of the weed, often leading to a less pleasant and stale taste and smell.
  • Mold and Bacteria Growth: If cannabis is stored improperly, especially in conditions with high humidity or moisture, it can become a breeding ground for mold and bacteria. Consuming moldy weed can be harmful to health, particularly for individuals with compromised immune systems.
  • Physical Changes: Weed can dry out and become brittle or feel spongy when you break it off, which can affect the smoking experience. 
  • Musty or Mildew-like Odor: Fresh cannabis has a strong, distinct aroma that varies among strains, often described as earthy, skunky, or fruity. Bad weed may lose this aroma and instead have a musty, damp, or mildew-like smell, indicating possible mold or decay.
moldy weed

moldy weed

While old weed does not kill you, the decrease in quality and potency, along with the potential for mold and bacteria growth, can make it less safe to consume, especially for those with underlying conditions.

How Long Does Weed Stay Good For

Based on the study by S. A. Ross and M. A. ElSohly, the concentration of D9-THC in cannabis decreases proportionally to the storage time. On average, the concentration of THC in the plant material decreased by:

  • 16.6% ±7.4 after one year
  • 26.8% ±7.3 after two years
  • 34.5% ±7.6 after three years
  • 41.4% ±6.5 after four years

That’s to say, the weed can stay good without losing potency for up to 1 year. After that, your weed can encounter significant THC loss, starting at 16% in the second year. Does weed get stronger as it gets older? Absolutely no. 

One more interesting finding is that, there is a variability in the percentage loss of THC over time. The study suggests that the initial concentration of THC might influence the rate of degradation, with higher initial concentrations degrading faster in the first one or two years.

how long does weed stay good

Last, the study highlights that storage plays a crucial role in the stability of THC in cannabis. Room temperature storage in the dark helps maintain cannabis potency for a certain period. So, let’s see how to store dried cannabis so you can keep it for a longer time. 

Optimal Storage Solutions to Prolong Weed Freshness

The choice of container plays a pivotal role in preserving the freshness and potency of cannabis. The ideal storage solution should protect it from light, air, and moisture, which are the primary factors that degrade cannabis quality over time.

how to store cannabis

  • Airtight Glass Jars: Glass jars with airtight seals are one of the most effective and accessible options for storing cannabis. They prevent air exchange and protect the contents from light, especially if the glass is tinted or stored in a dark place. Do not count on plastice bags, ever.
  • Temperature: The ideal temperature for storing cannabis is between 60-70°F (15-21°C). Higher temperatures can accelerate the degradation of cannabinoids and terpenes and can also increase the risk of mold and mildew development. Therefore, storing your cannabis in a cool, dry place away from direct heat sources is vital.
  • Humidity: The optimal humidity level for cannabis storage is between 59% and 63% relative humidity (RH). Humidity levels below this range can cause the cannabis to dry out, losing its flavor and potency. On the other hand, humidity levels above this range increase the risk of mold and mildew. 
  • Avoiding Light and Air: Exposure to light, especially sunlight, can significantly degrade the quality of cannabis. Similarly, excessive air exposure can oxidize cannabinoids, leading to a decrease in potency. Thus, storing cannabis in a dark, air-tight environment is essential. Don’t go for a refrigerator as it’s too moist for cannabis storage. 


While cannabis typically does not go bad like other homegrown plants, its THC content and overall quality degrade over time due to factors like light, air, and humidity. When appropriately stored, dried cannabis can remain in good condition for a period ranging from six months up to a year. As time passes, the potency of cannabis can significantly decrease after one year, with an average THC loss of 16.6% in the first year and increasing thereafter. Therefore, to enjoy the full benefits and experience of your cannabis, it's essential to store it correctly and use it within an optimal time frame. By following these guidelines, you can ensure that your weed remains as potent and enjoyable as possible for as long as possible.


About Ciki

Ciki has been navigating the digital world of SEO for over 3 years, applying her expertise originally in the software sector before turning her attention to indoor gardening. Merging her tech-savvy background with a passion for nature, Ciki offers a unique perspective on gardening, blending modern techniques with time-honored traditions.

2 thoughts on “How Long Does Weed Stay Good without Losing Potency

  1. dave says:

    are the filters serviceable ? what is the two bags that came with mine

    1. Ciki says:

      Which filters are you refering to?

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