The problem is in the thawing. Once thawed the embryo begins to germinate and must be planted or it dies. So no, you can't thaw them and then refreeze. What works for me is to only remove one or two containers at a time, quickly do what you need to do (like make your list) and then immediately return it to the freezer.

Better to do it in the winter outside.

Dave

Ok..thanks for the help!

I agree with Dave that you do your work with the seeds in a cold environment. For allium and herb seeds that I store in a chest freezer I pour out the seeds I need within the freezer, then reseal and close the container within the freezer.

But that method is at odds with at least one educator who recommends taking the bag out of the freezer and setting at room temperature for an period of time until all seeds come to room temperature. Then open the bag and remove the seeds that you need. His reasoning was that you want to avoid condensation of water on the cold seed.

I know my method works since I still have excellent germination on a pack of 9 year old onion seeds.

That's a good reason to refrigerating instead of freezing seeds if you want them to last repeat cooling cycles. I always refrigerate instead of freeze, but that was mainly because of convenience. Never heard that freezing was a once-only deal. Certainly, either way, let them warm up completely before opening to the air. You do not want liquid water on the seed, and you're likely to get that if cold seeds hit warm air.

Wow, I'm glad to find out that you can only freeze seeds one time. I was going to make a big mistake with my first stab at saving seeds. I was figuring on freezing but may go for refrigeration...or either freeze two or more separate, redundant seed collections...one for long-term storage and one to be used the next season. But being as different vegetables are planted at different times a broad collection of vegetable seed in one container might pose problems. I'm thinking the least headache (for my Stegosaurus-sized brain), though, will be with refrigeration.

One big container? For freezing you want multiple small, dated packets/containers labeled by variety, preferably in usable amounts based on your planting style. Those are placed into other containers by type of seed ex: beans (bush, pole, etc.), corn, onions, etc. Those containers can then be placed into the one big container for the freezer if you wish. The goal is finding what you want in and out fast.

Dave

Thanks for expounding on how you do it, Dave. Makes good sense. I was figuring on different packs for different varieties held inside of a larger container. I think the key point that I picked up from your post is "...based on your planting style". If I plant 30 tomato seeds a year figuring on a dozen transplants then 300 seed split up in 10 separate conatiners would cover me for 10 years...not that I'll be saving for that long, but you probably get what I mean. :) Naturally I'll be adding to these seeds with possibly the same variety or different varieties, so will end up with more seeds than I'm possibly capable of using...is this how it normally goes?<smile>

"is this how it normally goes?"

Yep, eventually you buy them their own freezer! ;-)

Dave

You're probably wasting time and money freezing tomato seeds. If you just keep them cool and dry like many other seeds they will be viable for ten years or more. I have over 330 tomato varieties, some that are hybrids which are quite expensive, and yet a lard can keeps them safe and readily available for multiple plantings. If your are worried about moisture just throw a bag of moisture absorbing gypsum in the seed storage container. And if your power is lost for a few days you don't have to worry about running a generator just to keep the seed freezer going.

Dave, I was afraid that might be one thing I was right about.<grin>

Barrie, I believe you about the longevity of tomato seeds. When I was first planning my garden I was going to order some tomato seeds. But I had some Mortgage Lifter and Brandywine (Pink) seeds in their packets closed up in a zip-lock bag that had sat on a shelf for a while that I decided to try. Both of the seed packets has "2011" printed on them. This was my first time starting tomato plants from seeds but these seeds germinated fine, though the ML were a little bit slower than the Brandywines for some reason. But, from looking at different storage-life lists of seeds on the internet and in books, it appears tomato seed has a longer storage/shelf-lives than a lot of other vegetables do.

The interesting thing is that I'm seeing tomato seed as being listed as having a 3-4 year viability when no special care is given them. I would imagine this at the least means something like I did such as storing at regular room temperature out of the heat (not in a hot garage), simple protection from humidity (a minimum of enclosed in a plastic baggie)....and not leaving on the dashboard of my jeep for a year or two. ;) ...my seed lasted easily for 6 years with those parameters.

But, keeping them refrigerated or frozen should definitely keep them viable for a much longer time, but does insert a little more complexity into the equation. Getting away from tomato seeds and other robust seeds it seems that keep the more fragile seeds cold or frozen would extend their storage-life greatly...but with the added complexity that would go along with it. To save these more fragile seeds I can see where freezing or refrigerating would be a big help...unless, like you said, the power goes out. Maybe a redundant system...freezing/refrigerating some and storing some "shoebox fashion". :) Now, not only do we need another freezer but need to add another closet on to the house...a walk-in one. ;)

330 varieties of tomatoes....WOWZA!!!!!!!!