How to Store Marijuana Seeds

Cannabis Seed Storage Guide
Author avatar By Tony Edwards
October 20, 2020

Millions of years of evolution + human ingenuity = successful home grower.

This editorial will look at the best way to store marijuana seeds, making sure they remain in top condition until you’re ready to sprout, plant, and grow them out. It will look at what containers to use, where to store weed seeds, and how to store weed seeds. It will be another small step towards becoming a happy and successful home grower. Perhaps the first question to tackle is; what sort of containers are best-suited to store your precious seeds?

What are the best containers for cannabis seed storage?

Above all else, the best containers are heat-proof and vacuum-sealed, though most of us can make do with ‘off-the-shelf’ solutions. The two storage containers listed below are not only cheap and readily available but also act as efficient containers for storing cannabis seeds both long term and short term, however, note that the second container functions better when used for short term storage.

1. Glass jars

Glass Jars

Glass jars are ideal, just make sure they’re air-tight, and don’t forget to keep them away from light. Plastic containers aren’t really recommended, the lids are often not as airtight as they seem, and they can create a ‘sweaty’ environment for the seeds.

Ensure you seal the glass jars correctly to limit or completely stop the flow of heat, oxygen, and excess moisture and store in a dark place so the seeds receive little to no light. Doing this will essentially slow down the aging process of the seeds, they are actually living things, and allow you to keep the seeds for longer before germinating them.

2. Ziplock bags

Ziplock Bags

Ziplock bags, though plastic, are a really simple solution, especially short-term. You can easily remove the air to create a vacuum seal (it won’t be absolutely vacuum-sealed, but good enough for temporary storage).

Once sealed, put the bag in any dark container and pop it in a drawer, away from dramatic humidity and temperature swings.

Choosing where to store your seeds

There are three factors vital to the successful storage of cannabis seeds:

  • Temperature
  • Light
  • Humidity. 

The best places will be permanently cool, dark, and dry – no big temperature and humidity swings and no danger of light contamination. Seeds can last for a couple of years in these conditions with no need for expensive fridges or specialized, laboratory-grade containers. Without these optimum conditions, however, the seeds will either use up all their germing nutes, fall prey to fungus, or germinate in-situ and die.

The way you store your cannabis seeds is just as important as the way you store your bud, but what are the best places to store marijuana seeds? What are the key ingredients to successful storage?

Short term storage

For short and medium-term storage, that is, a few weeks to two years, a cupboard or drawer is all you need. The same as with actually growing your cannabis seeds, you need to be aware of how to control humidity, temperature, and light, making sure the area you choose isn’t susceptible to big swings.

Tip: people living in areas with hot days and cool nights will want to store their seeds indoors, rather than outside in a shed or garage. 

Long term storage

If you plan on keeping your seeds long term, the best place to store your cannabis seeds is a heat-proof, vacuum-sealed container inside a second, ‘no-frost’ fridge. I use the term ‘second’ because your everyday kitchen fridge will be getting opened and closed far too frequently. This causes big temperature shifts and can lead to atmospheric moisture condensing on the surface of the seeds.

Tip: keep control of humidity levels by adding desiccant to the seed container before it’s put in the fridge. 

The top five seed storage considerations

  1. Humidity. Short to medium storage: 20 – 30%. Long-term storage: 8 – 10%
  2. Light. Keep your seeds dark, dark, dark. Light can trigger germination!!!
  3. Temperature. Optimum cannabis seed storage temperature is around 40 °F
  4. The Goldilocks zone. Avoid any major fluctuations in temperature and humidity, maintaining optimum conditions throughout.
  5. Oxygen. If possible, limiting your seeds’ access to oxygen can be beneficial, though not as important as the top four considerations on this list.

How long can you keep cannabis seeds stored?

When stored properly, cannabis seeds can germinate many years after they were harvested. They don’t come with a use-by date, but the longer they are stored, the lower the chances of successful germination. Seeds stored improperly may also take longer to germinate, up to a week in some cases. 

Basically, the best thing to do is plan your grow around obtaining the seeds. The fresher the seed, the better your chances of a prosperous grow. We know this isn’t always possible, especially with the number of free or cheap weed seeds dished out by amazing seed banks like the Homegrown Cannabis Co., so you need to know as much about storing marijuana seeds as possible.

Just one more thing…

Storing cannabis seeds in sensible containers is so, so easy, stand back in admiration, and then feel the color drain from your face as you realize nothing is labeled. ALWAYS label your containers! Do it now, before you’ve even ordered. Also, you should double-check there’s nothing but seeds (and desiccant, if necessary) in the containers. Make sure there is no dirt and definitely no bugs or pests of any kind. 

Shout it out!

A group of cannabis seeds

Employing an effective system for storing cannabis seeds is a vital string to any grower’s bow, but don’t keep this information to yourself. Sharing is caring and the more experience you gain, the more there is to share. Now that you know how to store marijuana seeds, you can share your knowledge with others!

If you have encountered a problem and need growing advice quickly, then why not sign up to the Homegrown Forum? This is a place for growers to give advice and share experiences with their fellow growers!

See you in the grow room!