It should last fine, as long as you store it in a cool/dry environment. I keep extra seeds in a small tupperware container in the fridge, and have no trouble with most seeds being stored for 5-7 years (yes, years). After that I tend to discard, but for stuff that I consider not critical (you know, those crops that if they don't work out too well you aren't terribly upset) I may keep the seed for longer, and generally most of it germinates fine.

I can't even imagine how much money I'd be wasting if I had to buy all fresh seed every season.

Ken

I agree. I grew corn last summer from 4 yo seed. Almost every seed that I planted grew but I do keep it in the fridge.

I just germinated some italian flat onions from seed that's dated 2002. (I store onions seeds in the freezer) They were a little slow to germ but they're looking great.

Thanks to you both!

I found a couple of internet sites claiming that open-pollinated corn seed that you save yourself is viable for only two years, and I was hoping that isn't true. I'm growing one OP and one hybrid and would hate to have to toss the rest -- who knows when it was harvested.

Most seeds can be stored indefinitely in the freezer at 0 degrees F in an airtight container. The seeds have to be dried first, by leaving them in an open container at room temperature for about 3 weeks. I germinated corn last year that was 23 years old. It seems to work for any seed that can stand to be dried. Some seeds can't be dried, like maple, oak, chestnut, and many tropicals.

Might consider testing your older seeds. Simply fill a pot with potting soil, water, add seed. Wait 5 - 10 days and you''ll know.

I usually put 10 seeds in each pot spread around. If I don't get a 70% germination rate I dump the seeds.

lilydude is right. Corn can be viable in the freezer for a long time. In 2006 I got 79% germination from corn seed that had been stored in the freezer since 1991.

Would you store seeds in the fridge if they're brand new and just waiting to plant them? I just have them in the bubblewrap packaging. I'd hate to lose them before I can even plant them.

Here is a link that might be useful: Sinfonian's garden

sinfonian, it depends on how long it would be before planting time and if I am going to be planting all the seeds. I definitely will store them in the freezer if I'm not planting all of the seeds.

Here is a tip for those who would like to try freezer storage. If you need some seeds out of the freezer, do not open the container while the seeds are cold. Moisture will condense on the cold seeds, which may greatly reduce their storage life. The correct method is to take the closed container out of the freezer, keep it closed, and let it thaw for at least 30 minutes at room temperature. By this time the seeds should be warm enough that condensation will not occur. Now you can open the container, remove the seeds that you need, and close the container and place it back in the freezer with the remaining seeds.

Any container that is airtight should work. I like ball mason jars, the big plastic peanut butter jars, and the big round plastic food storage containers with a tight-fitting cover. They all work fine.

If your freezer is self-defrosting, don't put your frozen seeds too close to the areas that defrost.

Don't forget to label your seeds.

Lilydude, that tip makes partial sense in that you would not want moisture condensation on your seeds. However, the thawing and refreezing cannot be good for the seeds either, especially when you consider that all warm air will contain some moisture that will enter the bag upon opening it.

I've been doing just the opposite in that I open the freezer bag within the freezer, dump out the seeds I need and immediately return the bag to the freezer. Have 7 year old onion and leek seeds that are germinating well using this method.

I'm not aware of a research study that compares these methods and I would like to use your method if seed viability is not altered because I am sort of forced to use all the seeds that I remove from the freezer.

I will note that I only have small seeds in my freezer in whirlpack plastic bags; onoins, leeks, Rosemary, thyme and lemon grass. I used to keep corn frozen but rather than going to the bother of saving many pounds of corn I find it simpler to just order my needs for the year. For all other seeds a bunch of metal lard cans have kept seeds for many years without any refrigeration. I have pepper seeds that are 17 years old that still germinate over 50%.

I once took a jar of bean seed out of the freezer and, absentmindedly opened it, removing some seed to mail, and resealed it. It only took, perhaps a minute. I then placed that jar in my closet, where it is relatively cool. The next spring, when I went to plant, I found that all of the beans in that jar were covered with a light layer of mold. I did a germination test and it was 0%! So I know that it's very important to avoid condensation. Perhaps Bmoser, your system works since you not only handle the seed in a cooler environment, but you also return unused seed to the freezer. Just an idea.

I've heard of corn, being stored in a closet for 20+ years and it having decent germination. In 2005 I received seed to a squash, which a friend had stored in his deep freeze, since 1986. I got about 95% germination. It was if it was only a year old!

George
Tahlequah, OK

bmoser, the only proof that I have that my method works is that I have seeds that are over 25 years old that still germinate. It's true that a little warm air gets in, but the moisture content is tiny, nothing compared to condensation. You don't want the seeds to have zero moisture content anyway. That's why I don't use a dessicant. Also, my method allows for a slow, controlled defrost rate for the seeds. This may be helpful in minimizing cell damage.

I have seen a corn seed that had to be well over 100 years old that came from corn husks that were being used to insulate the walls of a house here in the state of vermont, its a very cold climate here so they were in very good environment a pile of 100 or so husks produced 3 three stalks.

Anasazi corn is being offered now, and that variety is said to be 700-800 years old. Since that tribe/people are extinct, I'd guess the corn was grown from very old seed that (from my reading) seems to have been found in a dry cave or shelter area in the SW USA. That is remarkable if somehow corn that old was coaxed into germinating!

I would assume that with corn seeds, the higher the starch content, the longer they keep. So dent corn probably last longer than su sweet corn, and su longer than modern sh hybrids.

This is an old post so OP must have come to a conclusion of corn germination by now.

I’ll just reinforce drscott’s recommendation to do a germination test. I usually do it with 10 seeds between 2 small sponges banded together. This year I tested some sweet corn left from last year and got 20% germination... So I planted an acre at 5 times the rate with my Monosem planter and got almost identical stand as new corn seeded at standard spacing.

Regarding my previous post of removing seed from freezers I should correctly note that I do seed removal from the saved seed within the body of the freezer so stock seeds are not exposed to air temps above freezing. The removed seeds are then never returned; all are planted. This principle is similar to what cow artificial inseminators do when removing a vial of semen from a tank of liquid nitrogen. They pull a stack of semen straws up into the neck of the tank and remove one without exposing the rest of the straws to ambient temps.

Freezing seed instantly kills about a half ( in cannabis )

Micro ice shards form in the seeds endoplasm.

But the 60% viability of the rest of the seed is pretty well the same for at least our lifetime, if the seed is maintained frozen.

Defrosting and refreezing will lose you another 40%, and put you down to 36%.

Refrigeration will maintain viability between 80-90% for at least 10 years

Commercial cannabis seed is normally rated at 80% viability, so basically the fridge will maintain full viability for a generation.

I once killed ALL of the seed I had of a rare bean because I froze it before it was properly dry. It looked dry, but it had too much moisture in it. Now I always leave my seed out on a tray, drying for several weeks past when it appears "dry enough." Never have had another problem since doing this.

I wonder if cannabis is just unique among seeds or if more drying might not resolve the issue?

I din't think cannabis is specific.

It's just the seed I have most experience with.

I have a friend who has canna beans he froze back in the 70's and they still have good viability.

In those days the smoko was mainly seedy ( Zacatecas, Panama etc ) and was easy enough for him to store hundreds of anything interesting.

Good thing about the fridge is it isn't too big a deal if power cuts off and the temps raise.

I woujdgt enjoy defrosting a refreezing any seed I have that's valuable

I'm more worried about onion and corn seed viability, as they are both really short term if left in a drawer or cupboard.

What beans do you grow?

I haven't counted how many varieties I grow, but I have a special interest in the old Appalachian string bean (full bean) types which maintain tender pods for extended periods of time. They generally have strings, which once removed, leave a tender pod, sometimes with almost mature seed inside. The variety I killed wasn't one of those. Instead it was a Southwest desert variety called Tarahumara Pink Green Bean. I was able to recover my seed by contacting Native Seeds Search.

Here's a link to a thread I started on Spangler, an Appalachian Cornfield bean with the "full bean" characteristics. Some of my favorites are Tennessee Cutshort, Barksdale Wax Pole Bean, Cherokee Striped Cornhill, Ruth Bible and Frank Barnett.

2000 year old extinct Judean Date Palm seeds were found in the remains of King Herod's fortress and they grew and are now producing fruit as of last year. I found this interesting and thought I'd share.

Here you go. I can't remember where I saw this before, but I watched some fascinating video on the Judean Date Palm's recovery.

Ancient Origins Recovery of Extinct Judean Date Palm

"It is understood that freezing is an excellent seed preservation strategy. BUT, the seed must be COMPLETELY dry before freezing."

I agree. With very few exceptions (for seeds which won't survive freezing by nature) if seeds die when frozen, excessive seed moisture is usually the cause. The problem is there is no practical or affordable method available for accurately measuring the moisture% in small amounts of seed.

The use of desiccant to dry seeds helps to ensure a low enough moisture level - especially in a warm and/or humid environment. In my area, forced air heating in winter drives the indoor humidity so low, that all I need to do is leave the seeds out until then. If I see a lightning storm when pulling off a sweater, I can safely assume that the seeds are dry enough. ;-) A good rule of thumb is the break test; if a seed breaks cleanly when bent, or shatters when struck with a hammer, it should be dry enough for frozen storage. If it bends, breaks incompletely, or just crushes when struck, it may need more drying.

Regarding the removal of frozen seed... IMO the best method to ensure the safety of a large lot of frozen seed is to pre-package it in small small quantities. This could be small sealed plastic bags, within a larger sealed container (such as a freezer bag or mason jar). That way a single packet can be quickly removed for planting or exchanges - while still in the freezer - without thawing the whole container.

I should also add that at this time of year, the same precautions that apply to properly warming frozen seed, also apply to seed received frozen in the mail. As tempting as it may be to eagerly tear open that package, try to wait until the package/envelope warms to room temperature.

I can't remember, but I believe there ARE seeds that will not withstand freezing. Very few, but still. Can anyone help me here?

Good point about waiting to open until the seed package reaches room temperature. Why? Because cold seeds will condense water on them, which you do not want to happen. That can ruin the whole batch.

If the package is sealed up and stored where it is cool and dry, the sweet corn will store really well for 2 years. After that it likely loses some vigor, but may come up ok.

Ah, here's the answer to my question - what seeds can't be frozen. We're talking about what are called "recalcitrant seeds" (as opposed to "orthodox seeds"). Such seeds need to stay moist inside to be viable, and that moisture will destroy them when they form ice crystals. It would seem that we're not talking about vegetable seeds. These would include tropical rain forest seeds, as in avocado, mango, lychee, cocoa, and rubber.

https://saveplants.org/best-practices/difference-between-orthodox-intermediate-and-recalcitrant-seed/

See also https://en.wikipedia.org/wiki/Recalcitrant_seed

Corn is certainly orthodox.

The only vegetable I can think of with recalcitrant seeds is chayote squash... and much like some of the recalcitrant fruits, it is sub-tropical. You plant the entire sprouted squash, buried halfway, large end down (some on my kitchen table are sprouting now, but I can't grow them this far North). The most common fruit with recalcitrant seeds is citrus.

But I got a little off-track from the OP. If I store sweet corn in a sealed package, in a cool dark file cabinet, it will last 3-4 years. But since the sweet corn variety I like (Miracle) is becoming scarce, I bought a pound, divided it into 2-ounce bags, and froze all but two. Provided weather cooperates, I anticipate good germination until I run out.

Oh! I knew of a recalcitrant seed without knowing what it was called. Paw Paw seed will seldom grow once dried. It has to be stored (if stored) cool and moist.

I've heard of non sweet corn storing 20 years at room temperature, in a dark closet. I live where summers get extreme and we often skip AC to save $. Non sweet corn retains viability for me, at ambient temperature, in a sealed container, for about 4 years. Sweet corn would probably wane more quickly.

Also, though there is most certainly benefit to following strict protocols with frozen seen, I've been freezing my seed and using it for well over two decades, gradually refining my technique, as able. Initially, I simply dried my seed and set it, in sealed jars, in the freezer along with our frozen food. Over time I dedicated a small freezer to seed and set up bins with categories of seed in them, each in it's own sealed container (usually a plastic bag) inside the bin. I can see plenty of room for more refinement BUT I would caution against getting too obsessed with refined technique to the point that one never actually does frozen storage, or perhaps doesn't do it as much as they could. Even the most crude method I used was way better than what I was doing (storing seed in jars on a shelf in my living room).

For some time I've been struggling with memory issues and without doing frozen storage I would surely have lost a good many varieties. Some frozen storage, even if imperfect, is better than no frozen storage.