A general question:
If I buy remaining “2016” seeds on clearance, vacuum-seal them, and store them in the freezer, how good is their germination rate likely to be next spring?
I buy seeds at a discount each fall, and almost always have some left overs from the spring order. They all germinate very well, and I don’t even try to do much of anything to preserve viability.
I just throw them in a zip bag, with the date, and throw them in a card board box on a shelf in the basement where they don’t get wet.
I collect my seeds each year and put them in a small brown paper bag and mark the the type seed and year on the bag. I never put them in the fridge or freezer but they always do fine the next year.
My brother in law says he once found some seeds that were in his kitchen cabinet that were at least five years old and he planted them and every one of them came up.
I am aware that most people say to put them in the freezer though.
Do NOT freeze seeds unless you are 100% certain they are 100% completely dry.
If not, freezing will crack the seed and it won’t germinate. Keep them dry and in ziplocks or lidded Mason jars and they’ll be fine.
Rule of thumb: The LARGER the seed, the sooner it loses it’s viability. So, seeds for green beans, pumpkins, summer or winter squash and sweet corn should be replaced every few years. You’ll STILL Get SOME germination, but not as much as with fresh seed.
Tiny seeds like lettuces and poppies can last quite a number of years.
And don’t buy those 10 for $1.00 seeds at Walgreen’s, other than for ‘weedy’ flowers like Bachelor Buttons and Cosmos. Their germination rates are terrible. ;)
You asked about buying seeds, and this article is about saving seeds, but there is information on shelf life that you may find useful:
http://www.southernexposure.com/growing-guides/saving-seeds-home-use.pdf
There is a bunch of good stuff on that site if you poke around a little.
Depends somewhat on the variety, but even just storing them in the corner of my bedroom, I have 90% germination on seeds more than 10 years old. Go for it.