Seed Testing Season is Upon Us
Holidays? What holidays?
A seasonal heads up for those of us who grow our own seedlings — particularly those of you heading into your second sojourn, with a shoebox full of seeds that you only know as new. Well, sadly they’re not new anymore. But, to paraphrase the old guy in Monty Python and the Holy Grail, “They’re not dead yet!”
Unless they’re onions, in which case, yeah, they’re probably dead.
I know, it's the holiday season, blah blah blah, ho, ho, ho, dreidal, dreidal, dreidal, etc. But for gardeners, this is the season of planning. And part of the planning for seedling folks -- and particularly seed savers -- is testing seeds.
There's a word for non-viable seed: seasoning. And you can’t really know if a treasured packet of seeds has passed through that great veil of being, and into the realm of chicken soup flavoring, without giving them a grow. Oh sure, for certain types of seed that you use over multiple years, you can kinda see a decay curve in the germination rate. For the data lovers among us who track seed germination, you might make a graph like this, for, say, some tomato seeds:
Wait, you don’t document your seed germination rates with graphs??? Man you’re weird. As my Italian grandmother used to say, “Wassamaddafuhyou?”
JK. I don’t graph my seed performance, except to support cheeky substack posts. But let’s pretend I do. In that world, onions might look like this:
SAD!
Again, gardeners don’t actually do this unless they work in seed R&D labs. But you could. Just sayin’.
As you gain experience in this dicey cat & mouse game of seedy life & death, you develop a feel for the danger zones. For onions, things are straightforward — just assume that you need to buy new seeds every year. On the other hand, if you save seed from mustard family plants — say, kale, arugula and, you know, mustard — and store them in a cool dry place with no light, you can almost assume you will get five years out of them with reasonable germination rates. Sometimes as much as a decade.
So it does vary, but within ranges of consistency. Still, there is no way to know for sure that your seeds won’t let you down in a few months (really two months, for stuff like peppers). That’s not a lot of time. And at that point you don’t want to be wasting precious weeks flatulating around with dead seeds, then scrounging the internet for favored varieties while tossing food at your TV in frustration. Or, worse yet, begging for an intervention from your good friends at Central Bucks Gardeners (though we would be happy to help if we can). And if you are using untested seed that you saved yourself, then, let’s face it, you are just playing dangerous mind games with the universe at that point. Unless… Unless what, Tom?
(Let’s all say it out loud together:) Unless you test your seeds! So, how do you test seeds? This is very difficult, so read carefully... You plant some.
Hey, I know, this is mind-blowing, deep stuff. So take all the time you need to digest it.
But seriously, it is a pretty simple concept. We test our seeds from mid December through mid January while we are bored and dying for some sort of garden-related activity (and, if you’ve reached a certain age, to give yourself ample time to remember where you put all your seed-starting supplies…). Then we have plenty of time to replace any that have given up the ghost, and have retired to that great spice cabinet in the sky (particularly if they’re dill or coriander seeds).
You do need to be careful though. False negatives abound in this arena. More specifically, if, like me, you use a cool basement as a seed starting area in the spring, I strongly recommend that you move the operation to a warmer place in the house, just for a couple weeks. It’s not like you need tons of space or tons of light. But you do need warmth. Nothing tells a pepper seed to play dead quite like soil temperatures below 65° F.
Remember, you don’t really care about growing plants at this stage. All you care about is deciding whether this or that batch of seeds is viable. All that matters here is germination rate. So the testbed must provide ideal conditions for germination. Which, for the most part, just means warm seed-starting mix. You can safely worry about lighting, spacing, optimal container shape, etc., etc. in the spring. Heck, you can even use peat pots for this if you want, which I do not recommend when you start growing actual seedlings. This is a good way to give them a small purpose on their way to the trash can or compost pile, where they belong.
Two other brief pitfalls:
First, unless you have a greenhouse, resist the urge to save the seedlings that germinate. It is way too early to start annual seeds for next season. Just hold back your tears and toss them.
Second, none of this matters a whole lot unless you record your results somewhere. Make a list of the seeds you planted, the date, the variety, how many seeds you planted, and how many germinated. Then be sure to dispose of the seeds that you deem bad. Or, if you’re a hoarder, at least put them in a separate box labeled “Bad”. Or, in the case of dill, cilantro and a number of other things, move them to the kitchen pantry.
So, my seedling growing friends, you have been notified. It’s time to add one more thing to that over-crowded holiday to-do list. You will thank me in the spring.
Thanks for reading.
For more reflections about gardening and the broader life lessons it bestows on us, feel free to check out my online book, Life Lessons of a Backyard Gardener, which I am publishing here, one chapter at a time.