[radiohead]

A friend who works in a garden centre has been given a pile of last years unsold seeds and has kindly given me a selection of various salad leaves,squash,tomatoes,peppers and brassicas. Most have a sow by date of 2013.....but there are far more than I will use by then. I have heard and read mixed stuff on storing seeds in a freezer,it has been suggested they can remain viable for many years longer than normal. Anyone any experience of this?....does it apply to all seeds or just some?

[AndyRVTR]

No experience myself, maybe this will help...
http://www.ehow.com/how_5578968_freeze-vegetable-seeds-storage.html

[gobs]

I do not know anything either about fridge/freezer storing. However, I find a cool dry place in a well sealed container more than good enough. Most stay viable well beyond their sow by date.

Vegetables might not stay so too long, but once I read that duckweed seeds are viable for some 750 years.

And I have some decade old veg and flower seeds that germinate fine.

So, I personally would save the bother.

[GYO Girl]

In a previous job I worked as a university research technician in a plant research lab.  One of my duties was to maintain the university seed bank.  I had to sort, clean, dry, pack, freeze and keep records of seeds collected at our research field sites.

The important factor is that the seeds must be really dry before freezing.  The dryer the better.  We had a special dehumidifying drying cabinet for this purpose and the seeds spent about a month in there on average before packing.  If they are frozen with moisture still inside them they will split when thawing.

For storage we used special foil packets and a heat sealer device, but I imagine that polythene bags or a sealed box in the freezer would be fine, AS LONG AS YOU DRY THEM FIRST!  Oh, and bring them to room temperature for an hour or so before opening.

Hope this helps!

[Salmo]

I would be very wary of freezing seeds in a domestic freezer.

Seeds will germinate for many years but as well as the % germination dropping the vigour of the seedlings also drops. If the seedlings are less vigourous they take longer to emerge and are more vunerable to pests and diseases.

[gobs]

"We had a special dehumidifying drying cabinet for this purpose and the seeds spent about a month in there on average before packing."

Not that you want to put off anybody.

Thanks for that. One learns something every day.

[GYO Girl]

"We had a special dehumidifying drying cabinet for this purpose and the seeds spent about a month in there on average before packing."

Not that you want to put off anybody.

Thanks for that. One learns something every day.

Lol, yes I thought someone would pick up on that!  What I was trying to say that we dried the seeds to below room humidity.  In fact I did regular testing for moisture content as they were drying and they only went into the freezer once they had dropped below a certain % moisture.  Can't remember the exact figure but but was way below atmospheric humidity %.  We also had to leave the seeds for an hour after opening to re-absorb atmospheric moisture before sowing as they were dried to such a low level.  This way viability was preserved for many years.

I don't know if the professional seed companies dry to this level, the ones where the seeds come in an inner sealed packet.  If they are dried in this way, and the packets are unopened I can see no reason why they shouldn't store perfectly well in a freezer for several years.

[GYO Girl]

Oh, and do not try drying them in the oven, even at a low temperature - it won't do much for the viability! 

[mumofstig]

They store perfectly well, for years, in the foil packets you buy them in - as long as they are not stored anywhere hot, they don't have to be frozen or put in fridge.

Seeds that are frozen are for long term storage, it's really not necessary for normal uasage.
The date on the pkt is like BB dates on food...........a waste of perfectly good stuff, designed to make you buy more.

Last summer, I finally used up a pkt of mixed lettuce seed that was first sown five years ago, so imagine how long dry seed in a sealed foil envelope would last.

[bigben]

It might be worth a look at http://www.allotment-garden.org/vegetable/general/seed-storage-life.php
before you start. Some things like parsnips are notorious if they are starting to go out of date that going to the trouble of freezing them might just lead to tears.

[radiohead]

Thanks for all the replies...lots of useful info.
On balance I think I will stick to my normal practice of storing in a cool dry place...However I may be tempted to freeze a packet or two that I'm not too worried about for a couple of years and just see how they are affected