Whenever people ask me how long their seeds will last, I have a difficult time responding without going into great detail. The quick answer is that it depends on the seed. The oldest seed known to naturally germinate on its own was a date palm seed preserved in a jar found in Herod the Great’s palace in Masada, Israel. They dry and protected environment allowed this seed to stay preserved for over 2,000 years. Granted, Foundroot seeds aren’t biblical date palms but with proper storage they can far outlast their average storage rates.
The famous “Doomsday” Svalbard Global Seed Vault preserves over 10,000 seed samples buried inside a remote sandstone mountain packed under Norwegian permafrost. There, seeds are kept at −0.4 °F with 5% seed moisture. Below 45°F is plenty sufficient and we have found that most of our seeds are fine to be frozen–nasturtiums being the exception–as long as they are kept dry.
In short: Seeds can be safely stored in a cool, dark place at 32-45°F with low humidity.
Consistency is key. Fluctuation in temperature, moisture, and light will lower the lifespan of your seeds. As tempting as it is to check on them, remove seeds from storage as little as possible. When seeds are taken out, allow the entire container to come slowly to room temperature before opening the seal.
So, how do you create the specific conditions of a world class seed bank right at home?
- Glass Jar with Lid
- Silica Packet
- Paper & Pen
- Clear Tape
Be sure seeds are fully dry before storage. If saving your own seeds, allow seeds to fully air dry naturally and out of the sun. Find a clean glass jar with a well sealing lid. We use mason jars because they are bountiful in our home but any glass jar such as a baby food jar, salsa jar, or pickle jar will work great.
Create a great label for your seeds with all the information you may potentially need. Adhere the label in a place it won’t come off such as the inside of the jar or on the outside with clear tape. This will prevent the label from smearing if it gets wet.
Place a silica packet inside the jar along with your seeds. These can be found and collected from many food products. They are not necessary but if you live in a damp climate, they will certainly help take the extra moisture out of your seeds. If you still have the original envelope for your seeds, just place the whole thing in there. It is fine to store several seed packets in the same jar as long as each packet is labeled properly.
Place jar in a cool, dark, and dry place such as your refrigerator, garage, or basement. A root cellar will likely be too moist. As mentioned earlier, most seeds can be stored frozen but that is a personal choice.
Enjoy your seeds for years to come!
Even under ideal circumstances, seeds will not live indefinitely in storage. The better they are stored, the longer it will take for their germination rates to lower but they will lower over time. That being said, we don’t suggest throwing out old seed because you never know what these magical little plants are going to do. Even if you find an old pack of seeds under the couch, plant them out! Who knows what super resilient variety might be hiding in there.