How long do cannabis seeds remain viable? Marijuana seeds should be kept in a cool, dark place such as a basement or in your refrigerator. They should be in an air-tight container and must stay Knowing how to store cannabis seeds is important if you want to keep your seeds over long periods of time – how long do marijuana seeds last? Want to know how long marijuana seeds last? Keep on reading! Including tips on how to store them!
How long do cannabis seeds remain viable?
Marijuana seeds should be kept in a cool, dark place such as a basement or in your refrigerator. They should be in an air-tight container and must stay dry. Putting a cotton ball in with the seeds before storage can help suck up any extra moisture (this is why you often see little bits of cotton in seed breeder packs).
Heat and moisture ‘signal’ to cannabis seeds that it’s time to sprout, so as long as you keep the seeds in a dry, dark environment they can remain viable for years. I have heard cases of seeds sprouting after being in storage for 5 or even 10 years. However, you will notice that older seeds take longer to germinate than fresh seeds and a few of them may not sprout at all. As time goes on, fewer and fewer of the seeds will successfully germinate.
How Long do Marijuana Seeds last?
When it comes to cannabis seeds, many first time growers tend to have some sitting around from an old friend or baggie. With recent legalization, new growers are deciding to dust their seeds off and start their very own grow, but how long do marijuana seeds last before they won’t germinate?
A typical feminized cannabis plant can produce an enormous amount of seeds – hundreds, depending on how well the plant takes the pollen and how meticulous the pollination process is. It also largely depends on the strain, as some strains are capable of producing much more, especially if their flowers are larger and can hold more. But how long do they last once they’ve been harvested and dried?
How Long do Marijuana Seeds Last?
There are many different factors that come into play when it comes to cannabis seed lifespan, and the most important is conservation. If you’ve obtained your seeds from a seed bank and they come in their own packaging, when it comes to storage you can simply leave them in their packaging in a dark, dry spot; seed banks usually recommend planting within the year.
However, if you’re planning on crossing your own plants and making your own seeds, you’ll need to know how to harvest, dry and store them if you’re planning on keeping them for a while before germinating them; knowing how to store cannabis seeds properly is quite an important tidbit of information if you’re a professional cannabis grower.
The seed is undoubtedly just as important as the final result; without quality seeds, you won’t get quality results. Keep in mind that cannabis seeds are practically living beings ready to be brought fully to life. Many new growers don’t know that cannabis seeds require specific care, and the way you store your seeds can significantly affect their outcome. Check out our Cannabis seeds – Buy Marijuana Seeds section to find reliable strains.
Drying Cannabis Seeds
When working from the start you’ll first need to pollinate the flowers on a female cannabis plant and then harvest the seeds once it’s fully matured. Once you have your seeds you’ll need to dry them out before they can be stored or even germinated – they should be ready to harvest once they’ve gone a dark brown color or start showing dark stripes. Most people opt to dry their seeds by simply drying the flowers and harvesting the seeds once they’ve dried out – it makes them much easier to remove from the flowers.
How Long do Marijuana Seeds Last in Storage?
Once you have your seeds you’re going to want to store them correctly if you plan on using them down the line. In fact, when stored under perfect conditions, you can germinate 5 year old cannabis seeds successfully. Some astonishing cases have been reported of seeds lasting up to 10 years when stored optimally, although the germination times may vary wildly, taking much longer than a fresh seed. For home-growers, storing and maintaining seeds is quite important, and even more so for seed banks; 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.
Seed Storage: Light
One of the first things to keep in mind is that whatever container that you store your seeds in needs to block out all light. 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 too weak to germinate; even if they germinate they might have quite a hard time starting off.
Seed Storage: Temperature
The temperature at which you store your seeds is one of the most important factors. If you’re going for something short-term, you just have to make sure that they’re in an area with a stable temperature – do not store them somewhere where there are going to be temperature changes.
However, for long-term storage you’ll need to store them at around 6-8° – if you plan on storing a large amount of seeds, we recommend buying a small cooler for that specific purpose to keep them at a low, constant temperature; opening your fridge can cause temperature changes, so keeping them with the rest of your products is probably not the best idea.
Also, remember to use a blacked out container when storing in the fridge or a black bag to ensure that the lights inside don’t affect the seeds when opened.
Seed Storage: Humidity
Humidity is another incredibly important factor that can determine the success rate of your seeds. Relative humidity is essentially what causes seeds to germinate, so they’re quite delicate at this stage and you don’t want them accidentally germinating; keep relative humidity low in their container.
This obviously depends on your climate too, 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. As a general rule of thumb, we recommend keeping them in a low-humidity container, and if you live somewhere incredibly humid you might have to use specific methods to decrease humidity.
Cannabis seeds can germinate with a RH of 40-60%, and humidity higher than that can actually drown them and kill them. However, humidity ranging from 9 – 20% may also cause a myriad of issues such as insects, fungi, and even seed sweating due to excessive heat. The ideal humidity range in which to store your seeds is between 20 to 30% RH.
How Long do Marijuana Seeds Last
Taking into account the previously mentioned parameters, the best way to store your cannabis seeds for long periods of time is by vacuum sealing them and then putting them into an opaque container or bag so that no light gets to them. Keep them at a constant temperature of 6-8°. Some growers use products such as silica sachets to keep humidity down even if the outside temperature/humidity becomes drastically altered – this is a good idea if you live in more humid or hotter climates.
Keep in mind that if your seeds experience too much light or temperature changes they may end up using up their nutrient reserves, which would render them useless.
How long do marijuana seeds last?
And how to store them
If you’ve read our previous article on why you should grow your own marijuana, you learned that growing your own weed is fun, cheaper in the long run, and a sure way to never run out of something to smoke.
If you, like yours truly here are suffering from FOMO (for the non-hipsters among us: that’s short for “Fear Of Missing Out” 😉 and subscribed to a plethora of newsletters from various seedbanks to never miss out on a solid bargain, a certain luxury problem could occur: What do you do with all these newly acquired treasures when you don’t have an immediate use for them?
While nothing lasts forever, along the way I’ve learned that, if stored properly, marijuana seeds will remain viable for quite some while. With this article, I hope to finally answer that frequently asked question: how long do marijuana seeds last?
- How long do marijuana seeds last after storing them?
- How to store marijuana seeds
- What is the best place to store your seeds?
- Where do you keep your seeds in?
- Are there disadvantages of old seeds?
- How long do marijuana seeds last? let’s recap.
How Long do marijuana seeds last after storing them?
The short answer is several years or up to 5 years, depending on the circumstances.
The fact remains, that seeds exceeding that storage period are significantly harder to germinate.
So, you’ve scored big during the annual Black Friday sale and stocked up on all your favorites but then you remember, planting is months away.
Make sure your bargain isn’t going to cost you and ensure the viability of your seeds when planting time arrives with proper seed storage. It doesn’t take much, especially if you are storing seeds short term (less than two years).
If you plan to store your seeds for longer, it requires a few more steps to protect the long-term viability of the seed. But for short-term storage, a cool, dark, and dry spot are all you need.
Mother Nature’s designed them to respond to their environment within particular heat and moisture to signal the seed when it’s time to germinate.
Which, in nature is key to the survival of the plant, but not so convenient if you don’t have the intention of using them right away.
How to Store Marijuana Seeds
Marijuana seeds are living organisms which, when correctly stored, remain dormant. All seeds need to germinate is humidity and temperatures that are favorable.
Make sure your seeds don’t prematurely sprout by storing them in a spot that doesn’t have the right humidity levels and ensure the seeds are dry before sealing them in a container
Key factors for your storage conditions environment
Moisture is an especially important factor if you are freezing or refrigerating your seeds. If seeds are too wet, they can rot in the refrigerator or crystallize and suffer frost damage in the freezer. If you store seeds in the refrigerator or freezer, place the packets in an air-tight container and ensure you’ve properly dried the seeds, to begin with. As Cannabis expert Ryan Riley explains in Ryan Riley’s Growing Elite Marijuana
Consistency is key when it comes to temperature. So, you should avoid storing seeds in a spot that isn’t climate-controlled, like a garage or shed, where temperature can fluctuate wildly, especially during summer. 6 °C or lower would be ideal in terms of temperature. Unwanted fungi and bacteria in and on the seed may otherwise build up rapidly in a moist environment. High moisture levels and high temperatures will kill cannabis seeds as quickly as an invasion of microorganisms and insects, so be careful. How long marijuana seeds last, mainly depends on each 41°F / 5°C) temperature reduction in the storage environment. The recommended temperature is at least 41°F /5°C) (yes, this is slightly warmer than regular fridges). The cooler the temperature the more slowly seed vitality declines. This rule apparently continues to apply even at temperatures below freezing. At 41 °F (5 °C)
Light is necessary for germination; over-exposure may bring seeds to come out of their dormant state and encourage them to mutate. By keeping them in the darkness you ensure that they will remain dormant (provided that you’ve also taken the other requirements into account of course).
When you meet the above-storing conditions, storing cannabis for five years while maintaining high germination rates is entirely do-able.
Riley also advises making sure to label the container/package with the strain name, quantity, and date of storage to make storing easier.
In our article How to germinate weed seeds, we will teach you various germination methods that can make even the Methuselah’s among seeds sprout.
What is the best place to store your seeds?
Cool ✔ Dark ✔ That’s two out of three requirements down. As for moisture control: Experts swear by placing the seed in a closed container along with some uncooked rice to absorb any moisture (don’t forget to replace the rice regularly). A food-grade silica bag will also do the trick nicely.
Fridge is the best option, I think is to store them in refrigerators at a temperature between 6 and 8 degrees Celsius, and with relative humidity levels between 20% and 30%. And sheltered from light, of course. This spot checks all the boxes. In regard to the best place in your refrigerator, the crisper is a good choice, as it is a little warmer than the rest of the fridge.
One of the most popular places to keep your stash. The average freezer is about -15 °F dark and has a minimum of temperature fluctuations. A word of caution though! Some seedbanks keep a large stock, so you are at risk that the seeds you purchased were frozen and have now thawed. When the seeds thaw, they attract moisture. Re-freezing them causes crystallization and causes the seeds to perish!
Where do you keep your seeds in?
The freezer resolves the temperature fluctuations issue since you open it a lot less than the fridge door. Freezing seeds does not hurt them and can greatly extend their lifespan if done properly. . If you are saving seeds from a seed packet where you didn’t use all the seeds, keep the packet and put it into a Ziploc baggie.
We’ve now determined that keeping them away from moisture in a climate-controlled environment and limit the exposure to light to a minimum will significantly prolong their shelf life. Keeping them in the Ziplock bag they came in seems like the obvious thing to do. Or is there a better way?
If you plan on only storing them for a few months, cannabis seeds should do fine in a grip seal bag, placed in a mason jar, or some other type of airtight container. For more long-term storage, a vacuum-sealed package is a much more popular option. Many seasoned growers like to add a food-grade desiccant or some uncooked rice to their package as well.
What about a metal box or vault? That’s a big no. The metal will kill the seeds.
Are there disadvantages to old seeds?
Even if you’re organized, methodical, and careful about storing seeds, older seeds could be more difficult to germinate, resulting in more fragile plants, a thinner stem, and require more care and attention as seedlings.
There are a few tips and tricks to apply in order to increase your chances of successful germination.
- Sandpaper method: Some breeders use sandpaper (see video below) for older seeds. Lightly and gently scrape off the outer layer of the seed, creating micro-abrasions that help them absorb moisture more easily and then soak for 12 hours.
- Hydrogen peroxide: Soak the seeds in a glass of water with a few drops of hydrogen peroxide, for 24 hours at a temperature of 28 °C. The hydrogen peroxide softens the shell and facilitates the water’s absorption.
How long do marijuana seeds last? Let’s recap.
Saving cannabis seeds is a widely used method for preserving unique genetic varieties that one has particularly enjoyed or that worked very well when planted.
The most important factors when storing your seeds are keeping them cool, dark, and dry. Maintaining a constant environment with little or no fluctuation is vital to ensure the stability of your stored seeds.
You should bear in mind that humidity and temperature are the two most significant agents to have a quality storage system of marijuana seeds. Indeed, marijuana seeds are susceptible to their surroundings, since they dry out easily in a dry atmosphere and absorb moisture in a humid area. In every 1% reduction in the confined moisture, the life of the cannabis seeds inside the container in also prolonged.
So, there you finally have your answer as to how long do marijuana seeds last. Properly storing your seeds takes a little more effort than one would think but I ensure you, that extra care will pay off.
What’s your preferred way of storing your seeds? I’m interested in hearing your thoughts!
Educated by one of the best breeders in the Netherlands, I chose to combine my passion for writing with the fascinating world of cannabis cultivation. What are the best strains for which occasion, what are the effects, and how to use responsibly? Let me take you on a journey.