how to store weed seeds

Seed Storage 101: How to Store Cannabis Seeds

Not all of the seeds that you purchase always end up in the ground for planting the season that you purchase them, which means the left overs require storage. However, if they aren’t stored correctly, you risk losing that seed to environmental factors that could affect your crop – or maybe it won’t grow at all. This article is about how to correctly store your seeds until next season.

  • Environment
  • Storage Methods
  • Storage Containers
  • Desiccants
  • Preparation

So you’ve just received your latest shipment of 25 seeds from your favourite seed bank—and you only plan to plant 5 or 10 of them this season; or you’ve just finished this season’s harvest and you’d like to store the seeds you’ve collected for your next crop … Proper storage of cannabis seeds is an essential aspect of ensuring the viability of future marijuana crops.

There are two types of seed categories:

  • Orthodox Seeds – these seeds enter a dormant stage and will survive drying;
  • Recalcitrant or Unorthodox Seeds – seeds that will not survive drying and are susceptible to desiccation injury.

Cannabis seeds are the orthodox type, or desiccation-tolerant, and can be prepared for long-term storage without risking instability.

Key factors to consider when storing seeds are environment and container. Environment is important because moisture levels, temperature, and light exposure all play a role in the stability of your seeds, along with oxygen and ethylene concentrations. The container you choose for storage plays an important role in that the proper environment will be maintained if you use the proper receptacle. Hand-in-hand, these factors help ensure the viability of your seeds for either long- or short-term storage periods.


Environmental factors that affect the viability of cannabis seed are:

  • Moisture – reducing moisture exposure ensures seeds won’t prematurely germinate or become mouldy.
  • Temperature – fluctuations in temperature can lower a seed’s longevity significantly.
  • Light exposure – light is required for germination; over-exposure may cause seeds to come out of their dormant stage and encourage tissues to mutate.
  • Ethylene concentration – ethylene is an important natural plant hormone; seeds begin to produce ethylene immediately after exposure to water or moisture (another reason low moisture conditions are necessary during storage).
  • Oxygen concentration – lowering oxygen exposure will reduce or prevent seed respiration during storage, thus deterring premature germination.

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It is important to dry your seeds gradually and thoroughly before storing them—although not to 0% moisture, as this can result in the death of a seed. During ripening and drying, cannabis seeds will prepare for dormancy by slowing or stopping most physiological processes. Ideal moisture percentage is 2-3% and can be achieved by placing a desiccant in the storage container with your seeds. (A desiccant is a hygroscopic substance that induces or sustains a state of dryness in its vicinity (draws out water). Commonly found pre-packaged desiccants are solids that adsorb water, e.g., silica gel packs. These can be found at Wal-Mart,, or your local florist!). Rice is also known to be an effective desiccant, but should be replaced periodically. The use of a desiccant when drying seeds greatly improves their stability.

Keep cool, keep dark, and keep dry! Maintaining a constant environment with little or no fluctuation is vital to ensure the stability your stored seeds.

Storage Methods

The jury is still out on the best location for optimum storage results—each having pros and cons; here are the most common recommendations:

  • Refrigerator – your refrigerator is cool and dark, yes—but there is also a fluctuating moisture factor to consider each time the door is opened and closed. Storage in a refrigerator with a desiccant in an air-tight container is a viable option for seed stability and may adequately deter mould production. Storage toward the back of the fridge where the least moisture is present is preferable.
  • Freezer – despite popular belief, the freezing method itself actually destroys cells within the seed. Therefore this method is not recommended. There is special laboratory equipment that can be used for slowly bringing the seeds down to a temperature where they are not damaged, but most growers do not have this equipment. If you are going to use the freezer, put the seeds in an airtight, vacuum sealed bag or container with a food grade dessicant satchel.
  • Room Temperature – for storage lengths of a few years or less, keeping seeds in the proper airtight container at room temperature (such as in a closet or closed cabinet) with a desiccant is also satisfactory.

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Storage Containers

If the seed bank you order from packed your cannabis seeds in an environmentally controlled container with vacuum seals and moisture controls—such as a Mylar bag containing a desiccant, it may be best to leave their packaging intact for storage. If you are preparing your own seeds for storage, consider investing in a home vacuum sealer.

If you don’t have a vacuum sealer available, be sure the container you choose is airtight—such as a glass jar with lid. Most plastic containers are not recommended, as their seals are not always airtight; additionally, a water molecule is small enough to get through the pores of plastic containers—plastic containers are best for short-term storage only. On that note, plastic baggies, such as Ziplocs, are not recommended, as they allow light and temperature to fluctuate, and they are not sufficiently airtight.

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Containers with lids and bodies made from two different materials (such as glass body with a plastic lid, or plastic body with a metal lid) are not favourable, as different materials expand and contract at different rates. This permits moisture to intrude and/or exposes your seeds to temperature fluctuations.

Overall, glass containers are highly recommended for optimum storage conditions. They are suitable for long- and short-term storage. A glass jar with a glass lid and a ‘lightening closure’ is ideal—easily accessible and reusable—these containers are airtight and help maintain the constant environment your seeds require.


Using a desiccant inside your seed storage containers has several advantages. A desiccant will maintain moisture levels of 2-3% inside your airtight container during storage period; desiccants will also absorb excess ethylene produced naturally during the aging process, thus extending the life of your seeds. Silica gel packs are reusable, saving you time and money as well. Again, rice is also an effective desiccant, but should be replaced periodically for optimum results.

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  • Labelling – if you are storing several different strains of cannabis seeds, internal or external labels are recommended. Labels will also help keep light exposure to a minimum.
  • Desiccant – Place a layer of cotton or wool between the desiccant and your seeds to create a physical boundary between them. This helps absorb initial excessive moisture and ensures seeds will not be physically disturbed.
  • Seeds – Add pre-dried seeds to your container and seal.
  • Place seed container in desired storage location and wait!

Cannabis seeds are natural, living things and should be handled with care. When properly stored, you can expect your cannabis seeds to remain viable for approximately 5 years—perhaps longer. After 5 years, germination rates tend to drop; however, plenty of folks have successfully grown plants from seeds that were ten years old or more. Enjoy the fruits of your next harvest!

Cannabis seeds will stay good long after you buy them if you store them correctly. Read this article to find out how to do that.

How To Store Your Cannabis Seeds

Seeds are where all begins, the care you give your seeds will influence not only in how your cannabis grows but in the final harvest.

1. Cannabis Seeds

Before talking about how to store seeds we need to remember you that your cannabis seeds are alive. Before they germinate they are kind of in a state of hibernation, and like all living things, they can die.

When storing seed you want to provide optimal conditions to ensure they are still good until you’re ready to sprout them.

As we’re dealing with nature, you need to keep certain conditions or this can have an impact. Even though seeds have a hard shell and are fairly robust, you should have the following points in mind to avoid any kind of problems in the future.

2. Storing Seeds

When stored under perfect conditions, cannabis seeds can be viable for up to 10 years successfully. Seed storage is important for many reasons, either you’re a home grower waiting for the special occasion to grow that unique strain you just bought or seedbanks who need to stock seeds for the eventual sale.

Whatever your reason may be for having seeds, remember that taking care of them is one of the most important things you can do for your harvest. A badly stored seed may not germinate, and if it does it may not grow properly.

There are various parameters you’ll need to follow in order to store seeds long-term.

3. Ideal Conditions for Storing Seeds

There are three main factors that can affect seeds in a bad way:


If you’ve ever germinated cannabis seeds before, then you know that light is an important factor when it comes to the probability of the seed germinating or not. If your seeds are exposed to light for too long they may end up germinating before you’re ready to plant them.


Humidity is another incredibly important factor that can determine the success rate of your seeds as humidity is essentially what causes seeds to germinate. You don’t want them accidentally germinating, if they reach a certain humidity level they may start absorbing nutrients and end up too weak to grow normally, so you want to keep them in a relatively dry place.

This obviously depends on your climate as there are places that have incredibly high humidity and others that are quite dry, which can directly impact how you have to store your seeds.

If there is as low as 8% humidity in the container it can cause fungi to appear inside and outside your seeds, at 40-60% your seeds will sprout and beyond that, they can drown in less than a day.


The temperature at which you store your seeds is quite important. You’ll need to store them at around 6-8 celsius. You can keep them in your home fridge or even your freezer (however it’s usually not necessary).

We recommend storing them in the vegetable drawer or far back in the refrigerator and using a small cooler or something similar so the temperature doesn’t oscillate when opening the fridge door or if the power goes out.

4. Storing Seeds For Weeks

If you’re storing seeds for a couple of weeks it’s okay if you leave them in the original package as long as they are in a dark, dry, and cool place.

Usually, the package they come in is light-proof and water-proof, as long as you leave them in a relatively cool place like a drawer or something similar they will be good.

5. Storing Seeds For Months

If you’re storing your seeds for a couple of months it’s better if you store them in the refrigerator. This will guarantee the seeds don’t suffer from temperature swings. By keeping them in their original package or in a light-proof container you ensure they will be good for as long as you need.

6. Storing Seeds For Years

This usually applies to seed banks or breeders. If you need to store seeds for a really long time you can store them in a freezer. Even though it’s not necessary, it prevents you seeds from feeling the oscillation of temperatures even more.

You can still store them in a fridge, it depends on what you prefer and what options you have available. Ideally, you want to store your seeds in a cool, dark, and dry place.

Tip : When storing seeds in the fridge or freezer you can add silica gel sachets to ensure they’re completely dry.

High humidity can trigger fungi to grow on your seeds. If your seeds get exposed to light or rapid changes in temperature it will trigger them to use up their nutrient stores before they ever see soil, meaning they won’t have the nutrients they need to germinate.

7. In Conclusion

It doesn’t matter if you’re a breeder, a grower, or a seed bank, always keep your seeds following the tips above. This way you ensure your so precious genetics will still germinate when you are ready to grow them.

Seeds are where all begins, the care you give your seeds will influence not only in how your cannabis grows but in the final harvest. 1. Cannabis Seeds Before