[insert garden product] motif is a popular one and still sells everything from succulents to vegetables these days – hell, I use it myself sometimes.
But I stray from the point. If you’ve got a lot of seed packets kicking around, you may be wondering just how viable they are. Some seeds can last hundreds of years – others are defunct after a year in storage; yet there they all are, muddled together in various degrees of potential or impotence in a box under your bed.
Do you buy more? Do you ruthlessly cull? Do you take them to a seed swap and possibly disappoint young upthrusting gardeners thrilled to get their hands on German Strawberry tomatoes? And how many seeds does a gardener need anyway?
Let’s take a look at that pile of packets and create some order. Then we’ll test germination rates to ensure you’re not disappointed in the season ahead.
Pile One – The Cull
Toss out the seeds that you tried and didn’t like, or with which you had little success. There’s no need to fill the universe with rubbishy seeds.
Pile Two – The Swap
Swaps are fabulous places where you can pick up fabulous seeds from fabulous people, but they can also be repositories for other gardener’s so-so seeds. Don’t be part of that problem. Cull your herd first then set aside duplicate packets and the seeds which need to make room for new varieties you wish to try this year.
If there’s something you adore, and want others to adore it too, put a few in a Ziploc bag and label it for swappers. Then look up seed swaps in your area through local garden clubs, your extension service or – for the Washington DC Metro area – pegplant.com.
Pile Three – The Seed Bank
This is what you’re left with. The tried and true, or at least, the yet to be tried. Group them into loose categories to make planning easier (Roots, Greens, Tomatoes, etc.), and then test germination rates.
Germination Rate and Why it Matters
Germination rate is the percent of seeds that actually germinate in a given sample. High quality seed companies look for germination rates above 80%, but over time, rates decrease as seed becomes less viable.
All seed packets list the season for which it was packed. How long it will last is variable, depending on the kind of seed and how it was stored.
Testing your germination rate is easy and makes a lot of sense for direct seeded crops (those planted directly into the soil such as radishes, beans, carrots, etc.). If you are planning to sow a row of carrots, and your germination rate has decreased to 50%, you’re going to need to plant 50% more seed, or buy new seed, or be carrotless when a groundhog takes his 50% tithe in late June.
Testing Your Seeds
To test seeds, place a damp, quarter-folded paper towel on a small plate and put 10-20 seeds on the towel. The more you’re willing to spare, the more accurate your result, but this depends on how many seeds you actually have. This test doesn’t make sense for ancient packets of direct sow crops that have less than 30 seeds in them. Best to discard them and buy fresh seed.
20 Russian kale seeds await germination from a self-harvested batch of seed two seasons ago.
Otherwise, place another damp paper towel over the seeds and mist it every day, separating the towels briefly for air circulation. Look up the expected date of germination and add 7 days. Once that time has elapsed, count those that germinated and divide by the total amount. For example: 6 seeds germinated ÷ 10 seeds total = 60% germination. You’ll need to sow those seeds generously to ensure you have a full row.
For older seeds that are indirectly seeded into flats or pots, then transplanted later, I find it makes more sense to sow 2-3 seeds per cell and cull any extras early in the germination process (heartbreaking, but necessary to retain sanity). Indirectly seeded crops like peppers and tomatoes (particularly rarer varieties) often come in small quantities and taking out 10-20 seeds makes little sense.
Utilizing The Results
Once you know what you have and what is viable, you can confidently put in orders for new seeds, hoard seeds at seed swaps and sow your existing seeds in the correct quantity to reflect germination rates.
Or you can wing it.
If you choose Option B, I strongly urge you to go through your seeds as above and be ruthless in your sorting and categorizing. It makes for a happier, more organized gardener – even if half his seeds didn’t sprout. Some years I test, some years I wing it. Life doesn’t hand you the same cards every year.
The majority of garden seeds do best in an airtight container stored in cold, stable conditions in the dark. For those of us who are well past one container but still only have one fridge, a cool pantry or cupboard will also work. Personally I’m well past finding a large enough air-tight container that can store my collection, so I use a large wooden tray with filing markers and store them in the driest place I can find – my basement pantry. Not ideal, but I’m also not in the market to sell seed. Anything really precious – such as a seeds from a tree outside my alma mater – get stored in vacuum sealed bags in the freezer.
For More Information
I strongly recommend Terry and Mark Silber’s comprehensive and well-illustrated book on the subject Growing Herbs and Vegetables From Seed to Harvest as well as Christopher Lloyd and Graham Rice’s witty, information-rich banter in Garden Flowers from Seed. There are thousands of how-to books and websites out there, but I’m a sucker for those that give you a strong sense of the author(s) flowing right along with facts and figures.
Sort. Test. Strategize. Store.
It’s that time of year again. If you take a few minutes now, you can avoid disappointment and chaos later and be well prepared for a wonderful growing season to come. – MW