How to Germination Test Your Seeds

IMG_0685-2Looking through the seed packs of seasons past, it’s not always easy to know which seeds will reliably germinate. And which seeds to buy for the coming season. Here are some tips on how to test your seeds so you know which will be most productive and abundant for you.

Count out an exact number of seeds. We usually count at least 100, making the math easy: if 89 sprout and 11 don’t, you have 89% percent germination. Make sure you test at least 10 seeds, but the more seeds you test the more accurate your results will be.

Wrap your freshly-counted seeds in a moist paper towel, tuck them in a plastic bag and seal the bag. Label the bag with variety, seed count and date the test began. Keep the bag in a consistently warm place in your house (60-70 degrees F).

After a week, open up the bag and count the seedlings. Some seeds take longer to germinate than others; some seeds require unusual conditions to germinate, as well. But most garden seeds will sprout with this simple test within a week. And by the second week you’ll certainly have a sense of whether or not they’ll be reliable once the snows melt.


A couple of the common pitfalls


Relatively consistent 60-70 degree temperatures will suit many seeds. If seed is too cool (below 55 degrees F), it may not germinate. There are exceptions: claytonia germinates even in the refrigerator!

If seed is too warm (above 80 degrees F) germination also decreases. Brassicas and spinach are especially hesitant to germinate in warm conditions. Some crops, like lettuce and kale, germinate best when they chill in a refrigerator for three days prior to becoming moist. Other varieties (like our Habanada pepper) germinate best in temperatures that fluctuate 15 degrees F with a day/night cycle.


If seed is too wet, or especially too dry, they will not germinate well. Fortunately, moisture issues are generally easier to diagnose than temperature issues. A spray bottle is handy to moisten any paper towels that are too dry. Some common crops have moisture preferences you might not expect! Cucumbers, for example, prefer to germinate on the dry side.

And one more idea if you’re struggling

Potassium Nitrate (KNO3)

Some seeds prefer to grow in soil rather than a moist paper towel, period. For these we spray with a dilute solution of KNO3 (also called saltpeter) to simulate the chemistry they experience in soil that inspires them to germinate. For some seeds, this softens the seed coat in a way water would not; for others it breaks their dormancy. Tomato, parsley, chard and pepper are all crops we germination test with KNO3. Important note: it is possible to get a good germination test off these crops without KNO3. But if you are struggling, you now have an idea of how to troubleshoot.

Categories: Home Garden, Seeds, Tips | 4 Comments

Roger B. Swain: A Non-Compete Clause for Onions

“Since the best way of weeding
Is to prevent weeds from seeding,
The least procrastination
Of any operation
To prevent the semination
Of noxious vegetation
Is a source of tribulation.
And this in truth, a fact is
Which gardeners ought to practice,
And tillers should remember,
From April to December.”
~ The New England Farmer, vol.8, Boston, October 1829 *

Nowhere in the vegetable garden is this advice more apt than in the onion patch, where the least procrastination is the key word. Freed of the need to do anything for us, weeds will out compete nearly all of our annual crops, growing faster, seizing nutrients and water, and often overtaking their domesticated kin. In the kitchen onions may make cooks cry but in the garden row they are weaklings, handicapped by their short stature, slow growth, a limited amount of foliage and a root system that is both small and shallow.

Many years ago I tucked away a startling statistic about the consequence of weeds among the onions and not trusting my memory, I rummaged around in my library of vegetable books until I found it. It is on page 110 of Know & Grow Vegetables 2, the second volume in a pair of books written by J. K. Bleasdale , P. J. Salter and other staff of the National Vegetable Research Station in Wellesbourne, Warwickshire, England.

Oxford University Press published these two little books in 1979 and 1982. The research they cite is now at least 35 years old, but I have remembered the findings correctly. Onions in competition with weeds yielded almost 4% less after a single day. Leaving the onions unweeded for a fortnight reduced the harvest by more than half when compared to onions grown on ground that was kept clean all the time. I have always been fond of measuring things in fortnights. Why use miles per hour and not furlongs per fortnight? It’s no wonder that the fifty percent reduction per fortnight for onions has stuck in my mind all these years.

The issue of course is how does one keep the ground weed free? For starters, the onion bed should be laid out so that it is easy to reach all the plants without knocking over any onions that are in between. Hexagonal close-packing in a raised bed is fine, but the bed should be no more that two arm’s length in width. Then whether you start your onions from transplants or onion sets you should remove even the smallest weeds as soon as you spot them. The adage that the finest fertilizer is the gardener’s shadow applies to this activity. There is no substitute for regular scrutiny. Onions are not a low maintenance crop.

You can reduce the germination of annual weed seed by the use of mulches. On the Victory Garden television show the beds of Ailsa Craig onions, which we intended to reach three or more pounds apiece, were mulched with the fresh grass clippings taken when the lawn was mowed. Several inches of fresh clippings tucked right up against all the onions would dry, depriving weed seed the light and warmth needed for it to sprout. Of course, we were robbing the lawn of nutrients to do this, and having no bagger on my own lawn mower, I mulch my onions today with chopped leaves. These I rake up in the fall, shred and store them dry for the winter. Spread thickly among the young onion shoots they do not mat down or blow away. They dramatically reduce the amount of hand weeding.

When the onion tops have fallen over, the crop gets harvested and braided for storage. The mulch can be tilled into the soil and a cover crop can follow, or the weed seed will provide one. Nature abhors a vacuum, my father liked to say. But maintaining a weed-free zone for the onions when they are growing is what the nature of onions demands.

Roger B. Swain

* I thank Christie Higginbottom for passing this poem along. She recited it from memory at a recent NOFA winter conference. She was for many years the Horticulture Coordinator at Old Sturbridge Village, an 1830’s living history museum in Massachusetts so the poem is, as historians like to say, of her period.

Categories: Home Garden, Home Ground, Tips | Leave a comment

Roger B. Swain: Walking the Plank


Last winter, in a consignment shop in the next town, I spotted four squares of oak each bearing an odd iron clamp. The clue to their function was the impression left by a horseshoe in the wood. The horse that once wore these boards is undoubtedly long gone, but while it lived these “bog shoes” served to keep it afoot in soft ground. I am reminded of this now as I steer a wheelbarrow filled with compost along a narrow plank. It’s not myself I am trying to preserve but the integrity of the soil under my boots.

Frozen ground and dry ground both resist compaction, as does sandy ground and ground rich in organic matter. But the soil between these raised beds is none of these. It would only take a few trips walking back and forth on this path. even without a load, to transform it into hard-packed ground. The human heel reportedly exerts a pressure of 25 pounds per square inch about the same as the tire of a light pick-up truck.

The beds themselves are hardly less vulnerable to compaction from being trod upon. In my days as host of the Victory Garden television show, Kip Anderson, the show’s gardener, was always very tight-lipped whenever the director instructed me to climb into a bed so that I could face the camera while displaying a particular vegetable. Invariably Kip would get his spading fork when the shoot was over, and like the fellow tidying up behind circus elephants, he would carefully loosen up he ground wherever I had stepped.

The case for protecting the soil in the aisles is two-fold. First, the aisles are where water should be allowed to freely percolate as opposed to running off quickly. If your heat-loving eggplants are mulched with black plastic, this is how they will get their water unless they have a drip irrigation line under the mulch, which mine won’t. Second, how sure are you that you will never be planting in the aisle? To assure adequate wind pollination of corn, it may be necessary to periodically merge beds to allow for the planting of an adequate number of rows. Yes, the ground can always be re-dug, or re-tilled but why make work for yourself and tillage always results in a loss of organic matter.

And so one should always save scrap, untreated, lead-free lumber – the rougher the better – with which to lay out runways when the ground is wet. They will spread your weight in the spring, and if not picked up immediately will keep weeds from growing in the summer. The ground contact will mean that eventually, these boards will rot and no longer carry any weight, but they should rot and then they can add their own organic matter to the soil, like the horse that once wore those bog shoes, and as we who steer the wheelbarrows may someday do in turn.

P.S. One has only to write about trafficking on wet ground to create a drought. The spell of hot, windy weather that has followed will no doubt come to an end now that we have just set up an irrigation pump to draw water from the reservoir by the barn. It is the innate perversity of nature, my father liked to say.

Roger B. Swain

Categories: Home Garden, Home Ground, Tips | Leave a comment

Roger B. Swain: A Sparseness of Parsnips

Parsnips are the first harvest of the year, the sweeter for having spent the winter in the ground. But this year they aren’t.  As in absent, missing, departed, history, in short, gone. They were there in October when we dug the last of the carrots and beets. They were there when the ground, still bare at Christmas, froze so deeply that the waterline to the Hancock town library iced up. Parsnips are tougher than plumbing.  Parsnips are absolutely cold hardy, our spring reward for having survived all the blizzards and the school cancellations.

This  year, though, they are not. As in missing in action, AWOL, dearly departed. The day the snow banks receded enough to expose bare ground, I picked a spading fork up off its hook in the tool shed and went to dig the first one. In the thirty feet of double row, that’s all that remained. One. One single parsnip, the sole survivor, the one left behind to remind us of all the sweet roots we won’t be eating. Not this year the steamed and buttered, the baked, the pureed. We are too late to the feast. Our lovely parsnips have been eaten by others.

Unlike the bare shoulders of carrots or beets,  parsnip roots fatten up safely underground. I have seen deer hoof away enough soil to take a few bites, but not once the ground has frozen, or snow has buried the garden. This time, however, the roots have disappeared not from the top down but from the bottom up. As I turn over the soil I uncover a couple of crowns that are mere husks.

Voles like carrots, too.

Voles like parsnips. They like our carrots, too.

The snow that does such a good job of hiding the ground, also insulates it and provides cover to voles, those short-tailed, round-nosed,  plump little rodents in the genus Microtus. You can look up them up in your Peterson Field Guide to the Mammals. The culprit here is the one commonly called a meadow vole, among the most prolific of all vertebrates. The females reach sexual maturity in a month and can have a litter every month thereafter, with six or so young at a time. Woodchucks hibernate, chipmunks. too. Not voles.  They feed day and night all year long.  On spring lawns those half tunnels in the grass mark where their trails ran beneath the snow. The entrances to their burrows lack the pushed-up piles of soil created by moles, those completely unrelated tunnelers that have never once even bitten into a parsnip.

It was clear last fall, as I mowed the field with the tractor, that the vole numbers were up. Their population crests every two to five years. In an old field in Virginia, researchers once reported a peak density of 983 meadow voles per acre versus the 67 per acre when the population was at its minimum.  Hawks, owls, coyotes, foxes, weasels, snakes, shrews, and domestic cats all eat voles, but they do not prevent eruptions, and I take care to protect the tender bark of young fruit trees by wrapping their trunks in cylinders of quarter-inch hardware cloth. But parsnips?

Catching the culprit.

Catching the culprit.

Some people claim that they share their gardens with wildlife. Fifty or so to one, hardly seems evidence here of much sharing. Some will point out that I could have shielded the parsnips with the same hardware cloth that I used to save the fruit trees from being girdled.  Had the snow not been so deep for so long, I might have trapped the voles as I do to protect other vegetables during the growing season. Voles are a sucker for a chunk of apple wedged into the cup of one of those newer hard-plastic rat snap-traps, especially when the traps are hidden beneath an upturned nursery pot or box.

The loss of an over-wintered biennial crop is a risk that both the plant and the gardener take. For the plant, it is a summer’s accumulation of nutrients saved to make several feet of seed stalk and seeds the next summer. For the gardener, it is the starches and sugars to be consumed in a season of few other fresh vegetables.

The odds in this case were stacked against us both. The parsnip row ran alongside a  bed of daylilies and herbs, plants which no doubt provided voles with summer cover and nesting ground. This year they will rotate into a bed as far way from other vegetation as possible.

As for this spring’s lost harvest, let us say that it is out to lunch, or whatever the feedings of voles are termed. The sustenance that parsnips have provided not to us, but to the voles, will in turn pass on to those who will dine on the diners themselves. It’s a long way round. Next year let the odds be in our favor, let us be first at the table.

Roger B. Swain

Categories: Home Garden, Home Ground, Tips | 1 Comment

Home Ground with Roger B. Swain

Roger B. Swain


The steam rising off the pans of boiling maple sap, the receding snow banks out the sugar house door, the pair of newly-returned turkey vultures soaring overhead – these are all signs that spring, however delayed, is finally upon us. The spring peepers will soon be calling from the marsh at night, a chorus of optimism if there ever was one, and it seems a good time to introduce a new project, a series of seasonal reports and opinions on vegetable growing. This has come about through a chance encounter with Matthew at the Connecticut Flower & Garden Show where I was lecturing this winter. I stopped to admire his gallon jar filled with kernels of ‘Magenta Parching’ corn and one thing has led to another.

By way of introduction let me say that I have been raising vegetables on this southern New Hampshire hillside since I was a teenager, half a century ago. This has been purely non-commercially, although it has served me well as a practicum for my years as Science Editor of Horticulture magazine and as host of PBS-TV’ s The Victory Garden.

In my semi-retirement I have the luxury of reflecting on the whys as well as the hows of what we grow and eat. The booming enthusiasm for whole food and food that has been locally grown is both welcome and laudable, but it should not eclipse the homegrown. Just as recycling a grocery bag is trumped by reusing one, and in turn by not needing one at all, so the case can be made for the superiority of raising at least a portion of one’s food. It is not just the calories consumed or the dollars saved that matter. There is also the connection that is established to those who labor elsewhere to feed us.

Signs of spring

Signs of spring

To grow even a few vegetables at home is a lesson in ecology, and a reminder that the domestication of plants for our benefit requires that we, in turn, provide our plants with a level of care , from fertilizer to pest control, that their wild progenitors do not need. Finally there is the well-being that comes from a sense of self-reliance, and a generous measure of good health from the exercise. All these things we hope to expand upon in the months to come.

I am joined in this endeavor by Birgitta Keinanen, a source of inspiration and ideas, who, though younger than me, spent a dozen years gardening at Rosaly’s Garden, the oldest and one of the largest organic producer of vegetables in this state. As the first buds swell and we ready seeds to go into the soil again, wish us well, as we do you.

Roger B. Swain

Categories: Home Garden, Home Ground, Seeds, Tips | 1 Comment

Create a free website or blog at