[Guide] How to store your cannabis seeds correctly

Posted on 21. December 2020

Once you’ve bought your seeds from a quality online retailer, it’s important to know how to properly store the tiny seeds from your cannabis plants.

Storage has a crucial impact on the quality of the seeds over time, so knowledge of storage conditions is as important to you as cannabis strain and cultivation method.

Find out how to store and preserve cannabis seeds at home below.

You’ll get answers to all the practical questions about temperature, humidity and storage time.

Always buy cannabis seeds from a specialised dealer

It’s not just the storage conditions that affect the success of your seeds germinating optimally. Their quality is the main reason why you get the most out of your seeds.

You should therefore always buy your cannabis seeds (also called skunk seeds) from a professional dealer/producer. This is your guarantee that they have been produced according to all the rules of the art, and quality control will be carried out on a regular basis.

At a specialist retailer, you get both the best products and advice and help on buying the right seeds.

There are different strains of cannabis and the purpose of the seeds may differ from customer to customer.

In recent years, more people are choosing to use medical cannabis to treat illnesses and relieve symptoms.


Judging by the hard and firm shell of the cannabis seed, one could immediately assume that it can withstand any type of storage conditions.

This is not the case in reality. The seeds are living organisms containing active substances. This means that in poor conditions, the seeds will die and go to seed, and you will lose time, money and value. The worst conditions seeds can face are severe temperature fluctuations.

When you plan to germinate and grow your quality seeds optimally, it requires that they are stored both day and night under the right conditions.

It’s easy and simple to take good care of your seeds so you can get the quality and value out of them that you paid for.


When creating the best storage conditions for your cannabis seeds, there are 3 main conditions you need to consider.

It is about:

  • Light
  • Humidity
  • Temperature conditions

The very best way to look after your seeds is to store them in a dark, dry place with a stable temperature throughout the day.

If you have purchased cannabis seeds from a quality online retailer, you will receive them in a sealed package.

Leave the seeds in the airtight bag/container in which you received them.

Light, high humidity and extreme temperature changes are the main causes of seed death. This is because the seeds will quickly use up their stores of nutrients and thus ‘starve’ themselves.

The nutrient stores need to be activated only when you start the germination process.

If the humidity is high, it can activate the germination process or cause fungi to grow on the seeds and spoil their quality.


In principle, there is no expiry date for when cannabis seeds will become too old after being stored at home. Once you have created and found the right environment for your seeds, you can store them for years without any problems. Depending on storage conditions, you can – without any problems – keep fresh seeds for up to 5 years or significantly longer and still maintain a high germination rate.

However, it is essential to remember that the nutrients in the seeds will gradually be depleted over the time they are stored. This means that you get more pleasure and benefit from the seeds when you avoid leaving them for more than 1-2 years.

How long you expect to keep your seeds will influence the type of storage method and choice of packaging.

In general, it is said that cannabis seeds can stay fresh:

  • 2 years at 20-22°C (normal room temperature)
  • More than 2 years at 6-8°C


It is best to keep your seeds inside your home. Sheds, garages or workshops are more exposed to temperature fluctuations, and the environment in these places will change a lot depending on the external temperature conditions and air influences.

Many people therefore choose to store cannabis seeds in the refrigerator, which meets several of the requirements for both darkness and temperature stability.

The top shelf of the fridge is usually 4-5°C, which is close to ideal.


If you expect your seeds to germinate within the first week of receiving them, you can choose to keep them in a small, airtight bag or jar. However, if it will take several months before you sprout them, it’s a good idea to spend a little extra on storage.

For longer storage, the refrigerator is a good way to maintain the nutrient stores in the seeds. In the refrigerator, the temperature is the same regardless of the external conditions.

If you choose to use the fridge for storage, pay particular attention to the risk of moisture. Many refrigerators tend to have condensation. Make sure you keep the seeds in an airtight container and preferably at the back of the fridge, where they are less exposed to temperature fluctuations from opening and closing the fridge.

Freezer bags are good for storing seeds that are no longer in their original unbroken packaging from the retailer. With a freezer bag, you can remove virtually all air around the seeds, creating your own vacuum-sealed container.

A good and inexpensive alternative is to use storage tubes like the ones below. You can buy them here:
Seed storage tubes

Seed storage tubes
These small storage tubes, also used for liquid samples in laboratories, are hermetically sealed and protect your seeds from moisture.

Whether you have vacuum-packed your seeds yourself or you have received them in a good airtight package, you should store the seeds in a light-tight container, such as a black bag or jar.

When you open your fridge, the lights will come on. By storing your seeds in an outer, light-tight package, they are spared the effects of light.


Yes and no…

There is a proportional relationship between low temperatures and prolonged freshness/ability to germinate.

This means that the lower the temperatures at which the seeds are stored, the longer they can stay fresh.

Although some people recommend storing their seeds in the freezer for a long time, there are those who believe that it is actually harmful. In theory, freezing can cause frost damage to the living cells of the seed.

With specialised laboratory equipment, it is possible to lower the temperature of the seeds precisely and at a slow rate, eliminating the risk of frost damage. However, few growers have access to such equipment, so it is up to you whether you “dare” to use the freezer for seed storage.

However, for the vast majority of people, the refrigerator is a sufficient storage method, and since the frost damage argument is plausible, we do not recommend the freezer as a storage method.


  • Keep the seeds in the original packaging you received them in until use
  • If you have broken the packaging and sown some of the seeds, it is best to seal the remaining seeds in a freezer bag
  • Make sure you squeeze all the air out of the freezer bag with the seeds in it before putting them in the fridge
  • Always store your cannabis seeds in the dark
  • Choose a storage method that suits the expected time you want to have the seeds before use
  • Low temperature, low humidity and airtight packaging are key
  • Avoid significant temperature fluctuations – maintain a stable environment for the seed

Read also our
guide on how to assess the freshness of cannabis seeds