Cannabis seed storage is all about effective delay. Like tiny living time capsules, weed seeds are programmed to germinate when presented with the right sprouting conditions. Until then, they remain dormant. 

But they’re still alive, meaning they deteriorate over time and can also die.

To keep them in hibernation mode while protecting their inner embryos, you need to know how to store cannabis seeds safely. Read on to discover the best storage methods, ideal conditions, and more.


Why is storing cannabis seeds important?

Storing marijuana seeds is vital for various reasons. Whether you’re stockpiling, building an inventory, or preserving genetics, it all boils down to keeping your weed seeds viable for future germination.

In optimal storage conditions, they can still sprout after five years. Some growers even produce healthy crops with 10-year old marijuana seeds.

When it comes to cannabis seed storage, environmental factors greatly affect a seed’s ability to germinate (called seed viability). In fact, the wrong conditions can speed up deterioration, reduce longevity, and render your weed seeds useless.  

If they’re not stored properly, even high-grade seeds could get damaged, diseased, or worse—die.   

Whatever your reason, storing cannabis seeds correctly is vital for the success of your future weed crops and a fruitful harvest.     


How to store cannabis seeds


Ideal conditions for storing marijuana seeds

Weed seeds only have one chance to sprout successfully. Effectively storing marijuana seeds protects them against the following until they’re ready for planting:


  • High humidity levels
  • Temperature fluctuations
  • Light exposure
  • Oxygenation


Exposure to the above causes your weed seeds to activate prematurely. They’ll use up their nutrient reserves, and their shot at germination will go down the drain.

High humidity levels also trigger premature germination, attract mold growth and insects, and activate bacteria. 

That’s why storing cannabis seeds in a dark, dry, and cool place is essential. Temperature levels should stay between 41–46℉ but remember that consistency is key.

It’s also best to keep your cannabis seeds in their original packaging whenever possible. At SeedSupreme, our packaging is specifically designed to protect your weed seeds until you’re ready to germinate them.


Effects of humidity on your cannabis seeds

For optimal cannabis seed storage, humidity levels must stay within the ideal range. Here’s how relative humidity, expressed as a percentage, affects your weed seeds:



Relative humidity percentage

Effects on marijuana seeds


After 12 hours, seeds drown in moisture and wilt


Seed germination is triggered


Best humidity for weed storage (short-term)


Seeds may start sweating due to heating


After some time, could create a breeding ground for fungi inside and outside your seeds


Ideal humidity for long-term cannabis seed storage

Below 8%

Attracts insects, pests, and harmful microorganisms


How to store cannabis seeds

Now that you know all about temperature, humidity, light, and oxygen, let’s look at how to store weed seeds. Make sure they’re completely dry before using any of the below methods.


Paper envelopes

Thick paper envelopes are ideal for short-term cannabis seed storage. They block out ambient light and protect seeds from other environmental factors. Place your weed seeds inside with a few grains of uncooked rice or a desiccant pack to absorb any extra moisture.

Next, find a cool, dry, and dark place to store your marijuana seeds, like the back of a closet or drawer. Make sure the environment has a suitable stable temperature not more than 46℉. If you live in a region with an erratic climate, avoid outside storage. 


Vacuum seal bags

Using vacuum seal or Mylar bags is one of the best ways to store cannabis seeds long term. They can keep your seeds viable for up to five years or even longer, especially when placed in the refrigerator.

Vacuum seal your weed seeds, add some grains of uncooked rice or a desiccant pack,  and place the bag at the back of your refrigerator. This helps to avoid temperature fluctuations and light exposure. 

Storing cannabis seeds in the freezer is also possible, as long as they’re in a sealed container. Don’t thaw and refreeze them, though, as it’ll decrease seed viability.


How to store cannabis seeds


Glass mason jars

Glass or mason jars are airtight, making them suitable for long-term cannabis seed storage. 

Add a desiccant pack and a few cotton balls or a paper towel for moisture control. Next, cover the jar in opaque wrapping to block out the light, and you’re all set.

At the right room temperature, your weed seeds can last about a year. In the refrigerator, they can keep for a few more years. 


Airtight containers

Storing marijuana seeds in other types of food-grade plastic containers is also possible, as long as they’re airtight and light-proof or opaque. They’re more durable, so they’re also better than glass jars for freezer storage.

You can store your weed seeds in the container (like the glass jar method) or into a resealable bag first. Add a desiccant pack, and you’re good to go.    


Sealable plastic bags

Sealable plastic bags are another fantastic alternative for short-term cannabis seed storage. That said, they’re only ideal for room temperature environments and not refrigeration or freezing.

Add a desiccant pack or some uncooked rice grains, and store the bag in a cool, dark, and dry place where it won’t be disturbed.  


Cannabis seed storage FAQs

Do marijuana seeds go bad?

Yes, all seeds can go bad, meaning they lose their viability over time. Weed seeds can also rot with too much humidity. Proper storage and refrigeration or freezing slows down deterioration and increases longevity.


Can you store cannabis seeds in the freezer?

Yes. Storing marijuana seeds in the freezer is fine, as long as they’re in an airtight, light-proof, and durable container.


How long do cannabis seeds last?

Marijuana seeds can last for up to five years with proper storage. In some cases, they can keep for an entire decade.


How can you tell if a cannabis seed is still good (viable)?

Place the weed seed in a cup of water. If it sinks, it’s still good, while a floating one is less viable. There’s still a chance it could germinate, though, so see if it sprouts a tail first.

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