We have had a container (two actually) full of seeds that has been lurking in the back of our fridge for years. This is where we store our seed packets and there must be dozens of them, many dating as far back as 21 years old. In an attempt to try and make room for new seed packets in the already bursting Tupperware container we went through the seeds picking out the more recent seeds, making a pile of the old ones to get rid of. But in the end I could not bear to get rid of any seeds and ended up saving them, forming the second container of seeds. In an attempt to keep the older seeds moving along their way though, I decided to try out an indoors winter garden (I will write more about this soon). As it turns out, not throwing out the seeds was a great move for as I soon found, the seeds were incredibly viable despite their age. I regret that I did not record the amount of seeds that I planted (I plan on doing so in the future through!) but a vast majority of them sprouted without any lack in vigor noticeable to me. Intrigued I looked up the estimated date at which these seeds were supposed to have lost enough of their vigor to be deemed useless and the results were amazing. We had great success with these 21 year old Burpee seeds that according to multiple resources should have expired many years ago. Here is a list of the successful of 21 year old seeds I have tried:
- Basil
- Parsley
- Lavender
- Radish
- Peas
- Swiss chard
This says a bunch of things: that by storing your seeds in your fridge will greatly improve their viability, that the estimated dates that mark the limit of the seeds shelf life are under exaggerated and that Burpee sells high quality, long lasting seeds.
So as promised I did a germination test to get some quantitative results on the germination rates of some of the older seeds in our fridge. I hadn't been planning on doing one just yet but when I tried planted onion seeds and none sprouted it seemed like a perfect time to do so as I wouldn't be wasting any seeds that otherwise could have been used. The onions were more specifically Evergreen Long White Onions (apparently similar to scallions) that were packaged in 1990. I placed them in a damp paper towel on a plate, covered it with saran-wrap and left it out to find out how the seeds would fare. It was left at approximately 65 degrees for about 15 days before we began to count them up. The counting took forever and although the package advertised it containing approximately 700 seeds it most have been a very rough approximation for there was much more. After well over an hour of tediously separating the sprouted seeds from the
dead ones with tweezers, we added it all up and got the results. In total their were a whopping 1485 seeds 390 of which sprouted creating a (drum-roll) 26.263 percent germination rate. This is a surprisingly large successes rate considering they were not only 20 years old but that the package had been open for all twenty years. After doing some looking around on the internet I found out that onions seeds have one of the shortest shelf lives of all vegetables, all sites agreeing that they are good for only 1 year. All things considered the results amazing me as I was expecting a much smaller number especial after having had no success earlier in soil. Now you may be asking yourself how can seeds that have a 26.263 % germination rate have utterly none sprout in my previous attempt. There are most likely a few contributing factors to this but almost certainly the largest one was the temperature. My first go at growing them had been under the grow lights in our basement (the ones mentioned earlier) and being unfinished, the basement can get quite chilly in the winter. Seeds like warm soil when germinating and will fail to do so if it is below a certain temperature, causing the seeds to rot in the dirt. Doing a bit more looking around I found out that the ideal germination temperature for these particular seeds is anywhere from 60 to 70 degrees, a good deal warmer then the 54 of the soil in our basement. In conclusion the failure to germinate the onion seeds in the basement was almost without doubt due to the cold temperatures and therefore it is not surprising that when the seeds were tried out in the warmer up stairs that the rate correspondingly went up. But this isn't the first time I have had a difficult time getting many seeds to sprout or not even any at all and so this experience was what finally spurred us into getting a heating mat to put under
the seed trays. This was something that we had been meaning to get for a while now but had never really got around to and in the short time I have had it, it has already proven to be a great purchase (more on the mat is above).
