Seeds of Time: Why Heirlooms Matter

For hundreds of generations, humans all over the planet have been growing crops and saving seeds from their best plants to sow the following season. Seeds have a rich history and are very important to agriculture.

Laying Seeds

Saving seeds insures that you'll have a secure supply of treasured varieties, no matter whether the remain commercially available or not.

Photo courtesy fotolia/Bojan Pavlukovic

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For hundreds of generations, humans all over the planet have been growing crops and saving seeds from their best plants to sow the following season. No one had a degree in horticulture, and it's safe to say the vast majority of them couldn't even read or write since most of the work was done before the invention of the written word!

What's important is that these gardeners knew what they liked and needed and, over millennia, domesticated crop plants emerged. With each new season, these crops became a little earlier, a little more productive, a little more suited to the local conditions.

Heirloom seed types are thus products of their environment and of their growers' selection. They are often superbly adapted to the conditions under which they were developed — as, for example, the drought-tolerant varieties native to Southwestern agriculture.

Such is the immense work that had already gone into creating these precious crop plants when scientific breeding work began, slightly over a century ago, and this irreplaceable heritage furnished the building blocks of modern breeding.

Modern science, giddy with its initial achievements, was quick to tout the alleged superiority of modern lines, which were often only a few generations removed from the original types received from various native peoples around the globe. A credulous public bought into these claims and within the space of a couple of generations, the old varieties were cast aside in favor of “progress.”

Today, something like 90 percent of the varieties that existed at the beginning of the 20th century are extinct — just gone, nevermore to return. So it falls to the generations living today to try to salvage the tiny fraction that remains, and then pass along, renewed, to our posterity. Hence the designation “heirlooms.” What other legacy could possibly be more precious?

The fact that heirloom plants are open-pollinated means that all individuals within a variety share a fairly uniform genetic makeup. This in turn means the entire population “breeds true,” so long as no outside genetics are introduced into the population. That's a fancy way of saying: “You can save seed from heirloom types, generation after generation, just as growers have done for centuries.” You can't do that with hybrids!

There are lots of great reasons to save seed. If you save seed, you have the comfort of knowing that you have a secure supply of treasured varieties, no matter whether they remain commercially available or disappear. If pure food is important to you, you know just how the seed was grown, because you grew it. If you make careful selections of the best-performing individuals to parent the next generation of plants, over the years you'll actually be creating a distinct strain, uniquely adapted to your own climate and growing conditions.

Saving seed adds a new dimension to gardening, because it allows the closing and repetition of a natural cycle right in your own garden. It puts you in the driver's seat — you get to select for whatever traits and qualities that are important to you. You might also save some money over time, yes, but what's more important is you'll be stepping up to the plate and taking your turn in the endless chain of generations of growers and generations of crop varieties.

Lots of excellent books and articles have been written about the ins and outs of saving your own home-grown seed, including many in this publication. No very comprehensive instructions can be given in this article. There are plenty of details to be considered, and a little advance study can save years of trial and error. Fortunately, with just a bit of attention and planning, saving seed from most veggies is ultimately very easy. After all, your plants are all set up to make their seeds — you just need to know how to step out of the way and let it happen.

Seeds are produced within flowers. It's surprising how often experienced gardeners have missed this one crucial point. Some flowers, like roses or squashes, are very obvious, even showy. Others may be inconspicuous, barely noticeable at all. But in higher plants, the basic process is the same: Flowers are the plant's reproductive organs, and seed is produced only after an exchange of genetic material. The medium for this natural transfer is pollen. Pollen is produced within the flower, and gets distributed by wind, insects or many other means.

Pollination has to occur for seeds to develop. Exactly how pollen is transferred makes all the difference in planning seed saving. The reason is simple: For true seed, the pollen needs to come from a parent of the same variety. If a flower receives pollen from a flower of some other variety, the seed will be “crossed,” that is, it will not come out uniform to either parent. So you need to make sure that chance pollination is reduced or eliminated. This is most readily accomplished by isolating the parent plants by a sufficient distance that chance crosses with other types are unlikely.

The usual way is to isolate by distance; you simply plant your parent plants far enough away from other types so that chance pollination is unlikely. The distance varies from crop to crop — some crops, like common beans or lettuce, are almost always self-pollinating and chance crossing almost never occurs even when many varieties are growing in close proximity. Other types need more distance. Wind-pollinated crops like corn, amaranth, and beets need the greatest isolation distance, as wind-borne pollen can travel a mile or more!

Once you've protected your plants from accidental crossing, wait for the seeds to mature. Everyone knows what mature bean or pea seeds look like, but with some other types you have to let the fruit mature longer than you would for eating. Cucumbers and eggplants, for example, are usually harvested in an immature stage for eating. To get seeds, you must let cukes mature until they are very big, plump, and usually soft. Eggplants need to undergo a final color change — purple-fruited types will turn brown, white types will turn yellow and so on. It cannot be overstated: To get good viable seed, you need to allow full maturity before harvesting.

Harvesting consists of collecting mature fruits and extracting and drying the seeds. Some crops will yield dry pods or seed heads containing dry seeds. Beans, corn, okra, peas, and lettuce are examples. You simply pick the dried pods and shell out the seeds, or with lettuce, gently pluck the loose dry seeds from the dandelion-like seed head.

Other types are mature while contained in moist structures like tomatoes, peppers, squashes, and so on. With these, seed can be individually removed from the fruits by hand. Or, to get larger quantities, whole fruits may be crushed or scooped, and fermented briefly to allow the seeds to easily rinse free of the pulp.

In either case, be sure to allow your seeds to dry fully before storage. Beans and peas should be too hard to be dented with your fingernail. Squash and melon seed should snap when bent sharply — if they only bend without breaking, they are probably too moist. Allow drying to continue. A small fan can keep air moving around the seeds, securing the quick dry-down that is preferred for good viability.

Obviously, most seeds will be stored at least until the right planting time the following season. Successful seed storage is crucial because often you can save far more than enough seed to plant in one or two years' gardening. Storing the seeds frees you from having to save seed of a particular variety every season. Instead, you can save seeds from other varieties, which over time allow you to build up a very valuable home seed bank.

The best storage conditions for most common types is cool and dry. A common guideline is to add the temperature (in degrees Fahrenheit) plus the relative humidity. The lower the number you derive, the better. But so long as the total is under 100, you have adequate storage conditions. The figures given at right reflect average times that various crop seed may be stored, retaining good viability, in ordinary conditions figured according to the above equation. Often, seeds will store much longer than this, and with correct freezer storage, most seeds will be viable for decades.

Because so many crops need to be isolated for long distances, not all crops are suitable for seed saving in all locations. But what you cannot accomplish in your garden, someone else can manage in hers, and the converse is also often true. The solution is simple: trade!

The original and, to some, quintessential organization to distribute seeds is Seed Savers Exchange. A modest annual membership fee covers publication of the annual Yearbook, where hundreds of members list varieties whose seed they have grown and saved. Other members pore over the Yearbook and order fascinating seeds. You don't need to list anything to join and order from the Yearbook, and it contains thousands of incredible varieties, many of which are available nowhere else.

Seed swaps are becoming very common. They are often hosted by local garden clubs, university ag programs, FFA groups, homesteading groups — the list is almost endless. Home seed savers gather their carefully saved seeds and head to the swap, in keen anticipation of the horticultural treasures they hope to encounter. The excitement is palpable as gardeners talk shop. How bad was this year's weather? How much isolation do you need to protect peas? Why did my squash seeds mold? Other local and regional gardeners are your best resource, and you come away from a swap with so much more than new varieties of seed!

Online gardening forums have recently begun to enjoy huge popularity. There are dozens of them — some general, others specific to a single crop, like tomatoes, a particular region, and so on. But one thing they virtually all have in common is they all have a board for seed trading. Trading is usually done on the honor system, but gardeners tend to be good people and the vast majority of online trades go off without a hitch. Here are a few to get you started (but there are plenty of others):,,, and

More recently, seed libraries have emerged. A centralized seed bank is developed, and patrons borrow seeds instead of books. When the season ends, they are expected to return a new generation of the seeds they borrowed, preferably in larger quantities than they received. This offsets the occasional failure to make a return, allowing the seed bank to increase. Here are a few:,, and

Every region of the country has a history of growing and saving seed of unique, locally-adapted varieties. In fact, until the advent of the mail-order seed industry in the late 19th century, almost everyone grew and saved their own seed, trading it locally. Though much has been lost, there are lots of types still out there, waiting to be re-discovered and shared with gardeners the world over.

Such local heirlooms are most likely to be still grown and nurtured in rural areas, especially those where per capita incomes are low, often being cultivated and renewed by folks who’ve never heard of “heirloom seeds.” Growers like these maintain their treasured lines because they are often better than one-size-fits-all, store-bought varieties. You are apt to find them at farmer's markets and roadside stands. Or perhaps an elder in your own family has been carefully maintaining a family-held type for time out of mind.

Savvy home seed-savers keep a watchful eye, because there's no telling where or when something unusual will turn up. Don't be afraid to ask questions — original variety names may be lost in the mists of time, but often these seed-keepers will know that a family member brought the seeds with them when they emigrated from somewhere else, or at least will have some idea how long the variety has been in the family or the area.

Be sure to document as much information as you can, because people move or pass on, and a single chance encounter may be the only opportunity to learn the history of your “new” heirloom. Take notes, because memory sometimes plays tricks.

And if you are lucky enough to chance upon a local heirloom type, cherish it, nurture it and share it.

Here are some helpful definitions and tables that could help you increase your seed knowledge.

Heirloom, Hybrid, GMO

Heirlooms are open-pollinated varieties that have been around 50 years or more—sometimes, a lot more.

Hybrids are usually first- or second-generation crosses of inbred parent lines. For example, an F1 hybrid is not open-pollinated. That means that if you save seed from F1 hybrid parents, the plants grown from the saved seed will not breed true. Often they'll be nothing at all like the parents, and usually will be markedly inferior.

Genetically engineered varieties (GE or GMOs) could be open-pollinated or hybrid but all have had their genes tinkered with, with genes added artificially, often from some highly unrelated life form, including animals or even people! In nature, such genes virtually never mix, so GMO varieties are entirely artificial, new forms of life.

Crop Isolation for Beginners

Amaranth — Wind-pollinated, isolate by 1 mile (but few gardeners grow it); may cross with wild amaranth (pigweed).

Beans — Self-pollinated, isolate common beans by 50 feet; limas, favas and runner beans need ½ mile.

Cucumbers — Insect-pollinated, isolate by one-half mile, fruits should be fully ripe; they will be large, yellow or russeted, and usually very soft. Will not cross with melons or watermelons.

Eggplant — Self-pollinated, isolate by 50 feet, red varieties need 500 feet; allow final color change (full ripeness).

Lettuce — Self-pollinated, isolate by 12 feet, don't save seed from early bolters; may cross freely with wild lettuce, pluck dandelion-like seed before it scatters.

Melons — Insect-pollinated, isolate by one-half mile; seeds are ready when fruit is at prime eating stage, will not cross with cukes or watermelons.

Peppers — Self-pollinated, isolate by 500 feet; allow final color change (full ripeness).

Squash — Insect-pollinated, isolate by one-half mile; squash comes in four species, and the species rarely crosses with other species, so you can do one each of up to four species in one isolated garden.

Tomato — Self-pollinated, isolate by 50 feet; potato-leaf varieties like Brandywine need 500 feet.

Watermelons — Insect-pollinated, isolate by one-half mile; seeds are ready when fruit is at prime eating stage, will not cross with cukes or true melons.

Seed Storage Times

Here are some common seed varieties separated into appropriate average storage times.

1 Year: Lettuce, onion, parsley, and parsnips.

2 Years: leek, okra, pepper, and sweet corn.

3 Years: Asparagus, beans, broccoli, Chinese cabbage, carrot, celeriac, celery, and pea.

4 Years: Beets, Brussels sprouts, cabbage, cauliflower, chard, chicory, eggplant, kale, and pumpkin.

5 Years: Cucumber, endive, and muskmelon.

Read of Seed

Breed Your Own Vegetable Varieties by Carol Depp

Seed to Seed by Suzanne Ashworth

Organic Seed Production and Saving by Bryan Connolly

The Heirloom Life Gardener by Jere and Emilee Gettle

Randel A. Agrella lives, works and gardens in central Connecticut, where he also manages historic Comstock, Ferre and Co. An heirloom seed saver since 1982, he offers heirloom plants in season on his website, His articles have appeared in Heirloom Gardener since 2005.