The topic of how old a seed can be and still be useable has been bantered around for many years.
I have used leftover seeds from years past in my gardens for years. There are certain seeds that seem to stay fresh forever and other seeds that need to be used in a year or two.
From my own personal use, I prefer fresh carrot seeds and squash seeds seem to store forever. I have also noticed seeds that seem to be slow starters don’t hold stay fresh from year to year as well. I consider parsley to be a slow starter and a seed that does not germinate well the following year.
It also depends on how you store a seed. If it’s stored in a very hot humid area chances are high that the seed will loose it viability. And seeds will mold so they need a dry storage area.
For storing seeds I have used glass jars with lids and store in a dark place. And seeds that seem to have less viability or storage time I will place in the refrigerator to keep cool.
These two sites have more information on storing seeds.
Seed starting tips
- If you have seeds from a previous year you can save time by testing them for their seed sprouting viability.
- Use a paper towel and wet it. You want the towel damp, not dripping wet. Place 5 to 10 seeds in the moist towel and fold it so that the seeds are no longer exposed to air. I place the towel in a Styrofoam cup and place on the refrigerator or on a window that does not have a draft.
- Keep the paper towel moist, not damp. The towel acts as soil and will also hold in humidity and will make the seeds sprout.
- In 5 days check the seeds and see if you have any germination. If not wait another 5 days. Most seeds will show some sign of trying to sprout in 10 days (unless they are a hard-shelled seed and those usually need a different type of germination. These seeds are usually shrubs or trees)
- If the seeds are really not going to sprout there is a good chance they will show some sign of mold or have a peculiar smell.
If the seeds sprout, count the number that successfully sprouted to the number that didn’t and this will give you an idea of how viable the seeds still are. For example if 5 seeds sprouted out of 10 there is a 50% germination rate, which is fine.
If only one seeds sprouted out of 10 I would think of purchasing new seeds – unless the seed is rare or difficult to start.
I recently found an old packet of seeds from the 1920’s at an auction. I plan to try them just because it would be interesting to know if they are any good.
With proper storage many seeds will keep for years. Seeds that have been found in ancient digs have sprouted so give the seeds a try. Just try them before gardening season or in a spot in the garden you can replant easily if you have a poor germination rate.