How long do garden seeds last? How do you tell if your old seeds are still good? Let’s find out!
Wintertime is the season when these questions matter. The gorgeous seed catalogs arrive in the mail, tempting you with beautiful photographs.
But before you go crazy, it’s time to inventory your leftover seeds to avoid duplication.
How Long Do Seeds Last?
Some seeds have a longer life expectancy than others. Most last for a couple of years if stored in a dry, cool place.
- I have learned from experience that onion seeds are not much good after the first year but tomato, cucumber, and melon seeds can last 5 years or more.
- Brassicas and squash seeds are good for 4 to 5 years.
- Parsley, sweet corn, leeks, parsnips, shallots, and chives require fresh seed every year.
Seeds are living things and their viability is affected greatly by the way they are stored. Most experts agree on dark, cool, and dry conditions as being the best. We keep some of our seeds in the refrigerator but most are in open boxes in the dining room, probably not the best location.
How to Tell If Your Seeds Are Still Good
If I have a question about the viability of some seeds, such as those beans that someone gave me that they had kicking around since 2012, I will test a few.
This is as easy as placing ten seeds on a damp paper towel, folding it up, and placing it in a plastic bag. Put the bag in a warm spot and check after a week or so to see if any of the seeds have sprouted.
- 2 out of 10 means 20% germination—not too good, so I would just sow them more thickly than usual when planting or buy fresh seeds.
- If 8 out of 10 germinate that means 80%—not bad at all and I can get away with using them for another season.
Once you have determined what you need, you can shop with a clear plan in mind and be less likely to overbuy.
Have fun perusing the catalogs and dreaming of your best garden ever. Summer is just a page away in a seed catalog!
Reader Comments
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CORN SEED VIABILITY
I just tested two 9 year old heritage varieties of corn seed. Both had 90% germination but I did use a heat mat.
Heating mats increase seed propagation rates
Sowing seed indoors on heat mats tends to increase propagation rates. Just be sure to keep the temperature moderate (roughly between 65 and 70 oF) and not too high (higher than about 70), to avoid overheating the tender shoots. Thanks!
viable seeds
last year I came across some old castor bean seeds a k a mole beans. they were stored in a jar in a storage room. my dad gave them to me sometime in the mid 80,s.he used to plant them around the perimeter of his garden to stop mole damage. so I planted some in my garden last year and had about 75% germination rate. not bad for some old seeds.
Thank You!
I didn't get to my garden last year so I had my seeds left over plus my mom has a bunch of old seeds so I wanted to know if I could use those again. Your article helped a lot. I'll have to test out some of the old seeds from 2013 and try out my corn to see if it'll still make it this year.
Thanks
Just wanted to say thanks. Enjoy your posts, and articles. Saving seed is a fun project. My mulch passes on seed and last year we gained extra squash. Not this year they took over everything lol
Saved Seed
I have used seed from 2009 with excellent germination results. Some germination rates were a tad lower but nowhere near where what I thought they'd be and all I did was stick them in a freezer bag and forgot about them until I began going through boxes to downsize my home and BAM !!! there they were. At first I couldn't believe I'd been carrying packed boxes like that around with me. Truth to tell I honestly don't know why I had those seeds that long. i guess I'm what you might call a hoarder. Honestly, I was totally surprised by the viability of these seeds. Oh, let me just say this was 20 plus packs of a whole different variety of seeds and from various seed suppliers.
I was simply overjoyed to discover this especially since I live on a very low income.
Flower seeds
You talked about how long veggies seeds last...
How about pkgs of flower seeds?
Flower seeds
I have successfully kept marigold, zinnia, sunflower and nasturtium seed for at least two years. This spring willl be my third year with them and I'm confident I'll get decent germination. I buy these seeds in bulk - in one pound bags, so I'm happy that they keep for a few years.
canna lily
could you tell me what the seeds look like from this flower. One flower is gone I took a large thing out from the inside is this the seed
Canna Lily Seeds
Once the canna lily finishes flowering, it will produce a few seedpods that look similar to those of a chestnut tree or a burdock. Once these seedpods turn brown and dry, they are mature, and can be split open to reveal the true seed of the canna lily. The true seeds are fairly large (about the size of a pea) and are pure black in color.
Seed Inventory Time
Some of my leftover seeds, or seeds that I garnered from a previous crop, may germinate but seem to develop deformed plants or fruit. This is usually beans, corn, or peppers. Could this be due to them being hybrids?
Hi Mel,
Hi Mel,
If the seeds you saved are from hybrids they rarely will produce a plant that is like the parent. You could get something wonderful but usually it is a mutant throwback to a distant relative. To have any success with saving seeds look for plants that are heirlooms or open-pollenated. They will produce a plant that is the same as the parent. That said you do have to be careful of plants within the same species cross-pollenating - squash with gourds or one variety of tomato with another - those crosses sometimes result in a surprise! Your old seeds should not grow a deformed plant unless they have been damaged.
Rosemary plant
I have a rosemary plant that was blooming in a big pot until the cold weather, it's now in my garage, still looking and smelling like rosemary. How do I save it? Bring it indoors? Break up into smaller plants? Please advise. Thanks.
You must be psychic! I was
You must be psychic! I was planning on writing about wintering over rosemary next week! Here is my advice in a nutshell. Rosemary likes it cool and bright. If your garage does not fall below freezing and has a south window that gets lots of sun, you could leave it out there. Just be sure to water it when the soil feels dry. Don’t let it stand in water or the roots will rot. If your plant has more than one stem, it could be divided. During the winter rosemary is fairly dormant so don’t expect a lot of new growth. If the new growth is lanky it indicates that the plant is not getting enough light. If you need to winter it over in the house, place it in the coolest room near the brightest window. An unheated sunroom often works well as long as it doesn’t get below freezing at night. I occasionally wrestle my plant into the tub and turn on the shower to give it a good taste of rain. Misting will also help to hydrate the plant and discourage pests from setting up camp.