I don’t know if most people realize that seeds last more than one year – often 10 or more years. I never throw out a seed packet until it stops germinating. A seed’s life span is different for different types of seeds. While parsnips, and onions last only a couple years, I have had tomato seeds that are still viable after 15 years.
Here’s a nice seed viability table from James Romer at Iowa State University. It looks to me like these lengths of life expectancy may be when 50% of the seeds are viable. I think seeds are still pretty useful often down to 10%. So I would double the number of years listed here.
Approximate life expectancy of vegetable seeds stored under favorable conditions.
Vegetable | Years | Vegetable | Years |
---|---|---|---|
Asparagus | 3 | Kohlrabi | 3 |
Bean | 3 | Leek | 2 |
Beet | 4 | Lettuce | 6 |
Broccoli | 3 | Muskmelon | 5 |
Brussels sprouts | 4 | Mustard | 4 |
Cabbage | 4 | New Zealand spinach | 3 |
Carrot | 3 | Okra | 2 |
Celeriac | 3 | Onion | 1 |
Cauliflower | 4 | Parsley | 1 |
Celery | 3 | Parsnip | 1 |
Chard, Swiss | 4 | Pea | 3 |
Chicory | 4 | Pepper | 2 |
Chinese cabbage | 3 | Pumpkin | 4 |
Collards | 5 | Radish | 5 |
Corn, sweet | 2 | Rutabaga | 4 |
Cucumber | 5 | Salsify | 1 |
Eggplant | 4 | Spinach | 3 |
Endive | 5 | Squash | 4 |
Fennel | 4 | Tomato | 4 |
Kale | 4 | Turnip | 4 |
Watermelon | 4 |
How long seeds stay viable also depends on how they are stored. Recently, I have been keeping my seeds in the garage where it’s usually about 50 degrees in the winter and stays pretty cool in the summer too. I don’t have refrigerator space to store all my seeds – that would be the best place to store them – in a sealed container in the refrigerate. Another factor for viability is how often the seeds are move from one temperature or humidity to another. With each change the seeds wake up a bit and ask themselves if it’s time to germinate now. The more you can keep them sound asleep, the longer they will last.
I have to admit that I have a pretty big collection of seeds, over 500 packets. I just love seeds and love to try different varieties. A lot of my seeds are ones I have collected myself from plants I have grown. It is particularly easy to save seeds from squash, cucumbers, beans, tomatoes, peppers, and eggplants. Just make sure they are OP (open pollinated) and not F1 (hybrids).
I have a storage system that works pretty well. I have a box for vegetable seeds and another one for flower seeds. Inside the boxes I have pocket folders that contain the seeds. My flower folders are organized alphabetically and my vegetables are organized mostly by family. I have a folder for Brassicas that holds my cabbage, broccoli, kale, and other brassicas. I have another folder for Amaranthaceae that holds beets, spinach, Swiss chard and other amaranths. Tomato seeds get their own folder since I have so many. Peppers, eggplants, and okra share a folder.
I also have all my seeds cataloged in a long Excel list on my computer. This lists lets me know what seeds I have, how old they are, when they run out, what I plan to grow, and the dates I plant then each year. It was a lot of work to get all my seeds into the list – I did this about 5 years ago – but now it’s pretty quick to update it each year.
It’s such fun to write about seeds!