The Best Way to Store Seeds for Ultimate Longevity

Learn how to store your seeds in the proper conditions including how much light, moisture, and temperature fluctuations are acceptable.

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For me, garden planning is about to be in full swing! It is one of the ways I cope with those winter blues. Taking a little bit of time to decompress from the busy garden season is always essential for me. However, now that we are getting close to the new year, it is time to think about my past gardens, my future garden, and what I hope to get out of the upcoming growing season! 

My favorite thing to start with is a good look through my seed collection. I’ll be honest, this usually takes several days or even weeks because not only do I have to look through everything I already have, I also have to organize the chaos I left my seed packets in when I was in the middle of planting. Plus, dreaming about garden plans is one of my favorite pastimes. Planting season is always so busy and chaotic for me, organization tends to go out the window. However, I recently discovered a fool-proof way to store my seeds and keep the whole collection organized, so I have to share!

Photo Storage Case to Store Seeds

Photo storage cases are by far the best way I have found to store seeds. Not only do they create a protective barrier from pests or moisture, but the clear bins allow me to see what’s in each case. You can find them here on Amazon. This particular case has 18 individual cases for separating and organizing. I have seen people organize these cases in different ways. Organizing by plant type is my preferred method. I used my Cricut Joy to label the outside of the cases, as well.

You could also organize by planting times or season, alphabetically, or whatever suits your fancy. I like to grow different varieties of the same type of plant so keeping all the varieties of tomatoes together, for example, is helpful for me when determining which varieties I want to plant. 

When starting seeds, it is also helpful to have these sorted by type of plant because most varieties of the same plant need to be started at the same time, prior to the growing season. For example, at the 8 week mark, before my last frost, I know it is time to get my tomato case out and start all my tomato seeds. When my last frost has passed, I know it is time to get all my squash seeds out and directly sow into the soil in the garden. I have a full post on starting seeds, which you can find here. 

Do Seeds Go Bad or Expire?

You may be wondering what to do with the leftover seeds in those seed packets you half used last year. DON’T throw them away! Yes, seed packets have a “packed for” date on them. This is simply a requirement that seed companies have to comply with. This date is not a “best by” date or an expirations date. It is simply an indicator of the year the packet was packed in. 

Seeds can stay good and viable for long after their “packed for” date. In fact, I have had seeds well over 5 years old germinate successfully! The germination rate, or the amount of seeds that turn into seedlings compared to the amount of seeds planted, is highest when the seeds are the freshest. In order to combat a lower germination rate from an older seed packet, try dropping a few extra seeds in to make up for that lower germination rate. It is not always a given that you will have lower germination rates as your seeds age, but it is common.

There are a couple of best practices for storing seeds that will help give them the best shelf life and higher germination rates into the future. By keeping them dry, cool, and in a dark place, they will have the best viability, long term. 

Keep Your Seeds Dry

The number one most important thing to remember when storing seeds is to keep them dry. Moisture is the enemy when it comes to keeping seeds fresh. If you have enough moisture, your seeds may actually germinate while in storage, rendering them completely useless when it comes time to plant. 

Keep moisture out of your seeds by storing them in a dry place, away from possible water damage or excess humidity. I highly recommend not storing seeds on the ground in case anything was to ever spill/flood and the ground became saturated. I also do not recommend storing seeds outside. The outdoors can experience major fluctuations in temperature, humidity, and weather conditions that may affect the viability of your seeds. 

Airflow When you Store Seeds

Now that we know we should be keeping our seeds dry, let’s discuss airflow. Personally, I do not believe that seeds need airflow to stay viable. Read more here about storing seeds in an airtight container with the use of an oxygen absorber. With that being said, I have never used oxygen absorbers and I don’t think it is necessary. If you have oxygen absorbers at your disposal, by all means, use them. 

This being said, if your seeds contain moisture and you seal them in an airtight container, they have the possibility of molding. I have had this happen to me on multiple occasions. This has never happened with store bought seeds. This has only happened with seeds I saved from my own produce. I will discuss this point further in the section below: Seed Saving.

Keep Your Seeds Cool for Seed Storing

Another important storage consideration is temperature. Seeds stored in a cool place will last the longest. Storing your seeds in a garage or green house is probably not the best, unless it is temperature controlled. Garages and green houses can reach temperatures way outside of the normal range when it comes to the ideal storage temperature for seeds. 

My favorite location to store my seeds is in my basement. My basement stays a cool 55-60 degrees Fahrenheit all year round. We have a dehumidifier in the basement to eliminate humidity issues, as well. While this slightly cooler temperature is great for storing seeds, anywhere in your home is likely a sufficient temperature for viable seed storage. 

According to the experts, seeds stored in the refrigerator have the best shelf life. Read more here about proper refrigeration of seeds and how the humidity can be an issue with this storage method. Personally, I have not found refrigeration necessary but it is certainly a good option if you have the storage capabilities. 

Keep Your Seeds Away from Light when Storing Seeds

Lastly, keeping your seeds in the dark is another way to ensure the most viability in the long run. Light induces seed germination, which is the opposite of what we are trying to accomplish when storing our seeds. Light signals to the seed that it is time to start growing. If you are storing your seeds in a clear container, like glass or plastic, your storage location must be kept dark. 

As mentioned earlier, I store my seeds in my basement. Not only does this work well for keeping seeds dry and cool, it also stays very dark almost 24/7. There are no windows in my storage area and the lights are only on for a few minutes every now and then when we are in the room to retrieve something. 

Seed Saving

When I use the term “seed saving”, I am referring to the act of taking seeds out of the produce you have harvested (or purchased), to save for the future growing. Because this article is focused on the storage of seeds, I am going to keep this brief. Certain produce (technically called the fruits of the plants), contain easily visible and retrievable seeds; think tomatoes, cucumbers, and peppers. These seeds are ready to harvest at the time you are ready to eat the produce (AKA, when the fruit is ripe). Other produce like brassicas (broccoli, cabbage, etc.), will send up a stalk that grows and flowers, toward the end of its lifecycle. Once the flower dies and dries out, the seeds are ready to harvest out of the flower head.

Seeds Must be Dry

While there are many ways to save seeds from produce, there is one factor that always holds true. Seeds must be dry (fully, 100%, completely dried) before they go into storage for future growing. Seeds inside tomatoes and cucumbers, for example, are inside the liquid of the fruit. They live in a thick gelatinous coating to protect them. Ensuring the seeds are fully dry before storage is the only way to keep their viability. 

When saving seeds from home grown produce, set them out for several days before they go into storage. And by several days, I mean a few weeks, sometimes. Several weeks of dry time is probably not necessary but I typically just forget about them. I like to lay them out on a paper towel or paper plate. Remember to space them out and place them somewhere away from sunlight. 

Some tips for saving seeds this way. Label your seeds. I know you think you’ll remember but you may not, especially if you have multiple varieties of tomatoes growing. Also, put the date you started drying the seeds to gauge how long it takes. When in doubt, let them dry longer. If you put seeds into an airtight container with moisture still inside them, they will likely mold.

Additional Information

Don’t overcomplicate storing seeds. While the listed recommendations above are considered best practice, do what you can and just grow something! Don’t get discouraged if you don’t have the perfect storage system or perfect storage case to store your seeds. I gardened successfully for several years keeping my seed packets in a gallon ziplock bag in my dresser drawer in my bedroom; Little to no attention given to airflow, humidity, or temperature.

I mentioned earlier I have a post dedicated to starting seeds as well. This is a comprehensive list of everything you need to start your own seeds and save money compared to buying started plants from the store. I highly recommend checking it out here.

If you are feeling overwhelmed with where to begin your garden planning or seed collecting journey, start here. I laid out a quick list of things I have had repeated success growing, even when I had no idea how to garden.

I hope you enjoyed this peek into Life at Metzger Acres!