How Long do Cannabis Seeds Last

Before talking about how long stored cannabis seeds last and how they can also be preserved, we want to share how a weed seed is formed. First of all, pot strains have an outer layer called a covering that protects the embryonic bud, stem, and root contained within which are nourished by a sack of oil that is rich in nutrients.

As long as the shell of the seed remains intact and the embryo inside is not dried out or damaged, your seed can still grow into a large, strong cannabis plant. However, the shell will not last forever. When it dries and hardens, the top of the seed can crack and expose the embryo to potential damage. Another thing that can happen is that the seed coat hardens to the point that it no longer lets moisture through. In both cases, the seed is already in poor condition.

How to store our marijuana seeds

After being harvested and stored, marijuana seeds can last several years in some cases and depending on the circumstances, between 3 and 5 years at most. This type of seed becomes significantly more difficult to germinate if it exceeds these storage times.

Every time you buy seeds, it is good to request that they are fresh as is the case with Blimburn Seeds Bank where we have the best and freshest weed seeds for you. If you are going to buy seeds to grow in later months, you must make sure they have the necessary storage conditions.

If you plan to store your seeds longer, there are a few more steps required to protect the long-term life of the seed, but for short-term storage, all you need is a cool, dark, and dry place. Cannabis seeds naturally respond to the environment in which they are found, either with a certain heat or humidity in order to indicate to the seed when it is time to germinate.

When stored correctly, marijuana seeds are kept in good shape and can be grown without complications. It is necessary to ensure that the seeds have good humidity and favorable temperatures to germinate. You must make sure that the seeds do not sprout prematurely, so the measurement of humidity and having dry cannabis seeds is essential before storing them in a plastic container.

What factors influence successful storage of cannabis seeds?



Humidity is very important in the conservation of seeds as we have already indicated. If the seeds are too wet, they can rot. We say this because some growers keep their seeds in the refrigerator and make the mistake of leaving them in the freezer which affects the strains and causes damage from freezing and excess humidity. To avoid this, store the seeds in the lower part of the refrigerator, placing them in packages with hermetic bags and in an airtight container. Make sure to dry the seeds correctly before starting the process.


Some experts point out that temperatures are also important when it comes to keeping weed seeds in good shape. Therefore, you should avoid storing seeds in a place that does not have a properly controlled temperature such as a garage, shed, or even a closet of your house.

This is relevant because as you already know, temperatures in summer tend to rise unwanted fungi and bacteria inside seed packages can quickly accumulate in a humid environment. Therefore, high humidity levels and high temperatures will kill the cannabis seeds, so you have to be careful. Recommended temperatures are said to be at least (41 ° F / 5 ° C). Yes, it is a bit warmer than normal refrigerators. The colder the temperature, the more slowly the vitality of the seed decreases because the embryo that is inside the seed is more likely to die.


Light can affect marijuana seeds as they can mutate if exposed to excess light. By keeping them in the dark, you ensure that they will stay in good condition and will not have germination problems later.

The best places and tips to store seeds

The basement: This can be a good place to store seeds because they stay cool in good temperatures and also in humidity. Of course, you must be careful when summer arrives with its variation in temperatures and humidity. In addition, the basement is dark, therefore it meets the basic necessary requirements.


Humidity control: To control humidity, the seeds can be placed inside a closed airtight plastic container along with some raw rice to absorb the humidity. Another tip is to use a food-grade silica bag. This also helps to control humidity in a good way.

Refrigerator: This is undoubtedly the best option to store the seeds for this the refrigerator must have a temperature between 6 and 8 degrees Celsius and humidity levels must be between 20% and 30%. You can leave the seeds inside a black airtight bag and then put them in the airtight plastic pot to avoid having problems with the light.

The best space inside the refrigerator is the box where you leave the vegetables from the market because it is a little warmer than the rest of the refrigerator and will allow you to avoid damaging the pot seeds. We do not recommend using the freezer to store seeds because when you defrost them, moisture will be generated which will affect them.

What happens to the old seeds?

It is possible that you are a very tidy and programmed gardener and that you are very careful in conserving your seeds, but remember that old seeds can be much more difficult to germinate than new strains. In addition, it is good to point out that seedlings born from older seeds can be more fragile with thinner stems that may limit their development in the first weeks of growth. Because of that, they require more care and attention as seedlings.


However, there are some tricks that can be applied to increase the chances of successful germination. The sandpaper method consists of using sandpaper for older seeds where the outer layer of the seed is gently scraped, creating micro-abrasions that help them absorb moisture more easily. Then, the strain is soaked for 12 hours.

Another method used by advanced gardeners is hydrogen peroxide which consists of soaking the seeds in a glass of water with a few drops of hydrogen peroxide for 24 hours at a temperature of 28 ° C. Hydrogen peroxide softens the shell and facilitates the absorption of water, promoting a possible germination of the strains.

How to know if the seeds are in good condition?

Brown or dark color

When the seeds are dark brown, black, or gray, it is a very good sign. This means that the shell is intact which means that the genetic material inside has been kept in good condition. Viable seeds should also have streaks or spots around them. If the seeds are white or green, they are most likely still immature.

Waxy coverage and shine

Look closely at your seeds and see they still have a waxy coating as a healthy seed should have a slight sheen as if it had been oiled. This is an indication that the seed can still retain moisture so it will be easier to grow.

Hard seed coverage

If the seed is still healthy, you should be able to squeeze it lightly with your fingers without breaking, cracking, or separating the shell. When the seed shows any of the symptoms already described, it means that it has no chance of germinating and becoming a powerful weed plant.

To end

We have already shared how to conserve cannabis seeds, how they are composed, and what happens with the oldest seeds. Now you won’t have trouble or find yourself disappointed when trying to cultivate. The best thing you can do to achieve a satisfactory harvest of your own herb is to invest in fresh, high-quality seeds like the ones we have here at Blimburn Seeds.

Blimburn Seeds is a renowned seed bank that is trusted by hundreds of breeders around the world. Buying cannabis seeds online on our website is the best way to guarantee high quality seeds that will produce strong plants and beautiful harvests. You should also have peace of mind knowing that your pot strains are 100% guaranteed by Blimburn Seeds.

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