The Nearings' Sun-Heated Greenhouse

Helen and Scott Nearing find a more natural way to handle New England winter gardening by using a sun-heated greenhouse.

The Nearings' handle New England winter gardening by using a sun-heated greenhouse.

The Nearings' handle New England winter gardening by using a sun-heated greenhouse.

Photo By Fotolia/Alis

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A sun-heated greenhouse is a project that practically any family can work at and benefit by. The undertaking can enlarge the possibilities of income.

The Nearings' Sun-Heated Greenhouse

It was on a chill day in the autumn of 1932 that Helen and Scott Nearing turned their backs on New York City and signed an agreement to buy a run-down farm in Vermont's Green Mountains. And there they lived for the next 20 years . . . clearing brush, building honest stone structures, and raising most of their own food in gardens that were unbelievably vigorous and productive for New England.

It was a Good Life. So good that when "developers" began turning the slopes around them into a ski resort . . . the Nearings pulled up stakes, moved to a rocky inlet on the coast of Maine, and started all over again.

And that's where you'll find Helen (74) and Scott (94) today . . . still clearing brush, building honest stone structures, and raising most of what they eat in gardens that are unbelievably vigorous and productive for New England.

Two of MOTHER's people were fortunate enough to spend a day with the Nearings this past fall and, as some of the photos accompanying this article attest, they had more than a little difficulty just keeping up with Helen and Scott as they followed the two legendary homesteaders around.

In the first place, MOTHER's editor and photographer couldn't have slept late if they'd wanted to. Why? Because Scott was up at dawn and spent the next hour (right outside their bedroom window) splitting wood for the Nearing's two wood-burning stoves.

Then, after a simple but hearty breakfast, both Helen and Scott put in a few hours mixing concrete and setting flagstones into the floor of the combination storeroom/garage that they're currently building. This, of course, was just a little light limbering-up exercise to give them an appetite for their lunch (again simple . . . but monstrous!). After the midday meal, of course, the Nearings slowed down considerably . . . for them.

Which is to say that Helen only picked a couple of bushels of late beans from their garden, went to town for the mail, rummaged through a small storehouse of the books they've written and hauled several boxes of the titles back to their house, took care of other business, ran errands over what seemed to be half of Maine, and — finally — delivered MOTHERS representatives to a distant airport.

And Scott? With a little help from two or three assistants approximately 70 years his junior, Scott idly whiled away the afternoon digging a couple of hundred buckets of grass and weeds from the Nearings' blueberry patch, oversaw the transplanting of lettuce and other vegetable sets into their sun-heated greenhouse, explained the finer points of wholistic gardening to a few people, and otherwise kept the homestead under control. (That's the trouble with these vegetarians. They can still do so damn much at 94 that they make this generation's 20-year-old fast food munchers look positively sickly and infirm.)

But that's not what the following excerpts from the Nearings' latest book (they've written more than 50) are all about. These excerpts are about the Nearings' sun-heated greenhouse that Helen and Scott use to supply themselves with fresh green vegetables right through the heavy snows and frigid winds of a New England winter.

The Nearings really know how to feed themselves well in a rugged climate without using energy — intensive gardening systems, as the following snippets from their new book prove . . . and we hope this tiny taste of Helen and Scott's genius will inspire you to run right out and buy their new $6.95 paperback — Building and Using Our Sun-Heated Greenhouse — for your very own. It's worth far more than its price.

We began our winter gardening in an unheated greenhouse almost by accident. A small seedling (or seed) got lost under a bench, and in early January, going by chance into the ice-cold building, we found a flourishing, lush, and sizable lettuce plant growing through a clump of dry leaves. It had survived, unwatered and untended, through several months of outside freezing, in a sheltered but chill corner of a cold glassed-in building.

If this could happen, uncared for and unbeknownst, why could not more lettuces, and other plants, survive, under better conditions, still without artificial heat? We were launched on an experimental period of greenhouse building and planting that has provided us with fresh green things through thirty winters of freezing and below-zero weather.

Without question, plant germination and growth is checked by cold weather, and only certain plants can survive. Very low temperatures will kill almost any growing thing eventually. But there is a wide margin, and our experiments pointed up the plants that will not be killed by low temperatures.

Almost all of our gardening experience has been in the North Temperate Zone, taking advantage of summer sunshine when we can get it, and taking cover as cold blasts from the north and east strip the foliage from trees and crumple down green crops in the garden. One of our chief aims in gardening is to find those plants that can remain succulent and edible throughout the coldest weather.

Timid In The Beginning With Winter Gardening

We were timid in the beginning of our early experiments with winter gardening. Getting up around daylight and going into the greenhouse at the point of maximum possible frost damage, we saw plants of lettuce and Chinese cabbage and celery, escarole, collards, chard, and radishes limp and wilted as though their life span were near its end. Going back a few hours later, after the sun had had an hour or two to melt the frost on the greenhouse roof and windows, we found the semi-wilted plants revived, standing up sturdy and strong.

After a few such experiences we realized that we had seriously underrated the frost-resistant capacity of semi-hardy plants. If a greenhouse looks like a graveyard early on a zero morning, close the door, wait until the sun has burned off the frost covering, and you may be astonished to observe the comeback.

Plants Freeze Easily

Most cultivated garden plants freeze easily. A garden of beans, corn, tomatoes, and squash can be wiped out by three or four 28 degree night temperatures. Other garden plants such as Chinese cabbage, some lettuces, and celery often can stand up against temperatures as low as 20 degrees. For years we have been able to carry over kale, brussels sprouts, leeks, parsley, and even spinach in the open garden if a blanket of snow comes before the deep freeze.

The winter of 1976 — 77 was one of the longest continued cold spells, with no alleviating thaws, that we remember. The cold started in November and carried on through to March. We had to leave our farm early in December for a lecture trip and did not return till late January.

We found two broken windows in our greenhouse and one of the garden gates wide open and frozen in solid ice. Nevertheless, our sun-heated greenhouse, minus two broken-out windows, and heated only by a few days of pallid sun, was able to supply us with:

1. About 100 elephant leeks, still edible and delicious in mid-February
2. Several dozen celeriac roots
3. Two dozen roots of viable green parsley
4. A score of Pascal celery plants (the outer leaf stems were frozen, but the growing centers were lively and green)
5. A dozen small escarole plants that were lightly covered with dry autumn leaves
6. Several dozen half-grown lettuce plants: Simpson, Oakleaf, and Buttercrunch
7. Three red chard plants.

This is hardly noteworthy in comparison with the glorious green that has carried over for us some winters, but it shows what might be done in a winter greenhouse by gardeners who stayed at home and took care of their winter gardening.

We do not recommend leaving a greenhouse without care. We believe that if it is given daily attention the plants which it shelters will be in better condition than if left in total neglect. What we are propounding is the apparent capacity of certain untended plants to survive in continuous sub-zero weather.

The simple, cheap, unheated type of greenhouse that we have evolved adequately protects certain selected greens all winter. With moderate heat in the garden in summer and glass protection through the coldest of the winter months, we have lengthened the season so that we can feed ourselves year round on growing green things. It is on the basis of almost half a century of experience with growing lettuce and other plants in a cold climate that we base our argument concerning the possibility of year-round gardening and especially the possibility in a glass-walled unheated greenhouse.

A Greenhouse Extends the Growing Season

There are many weeks in a New England gardening season when temperatures hover around freezing. A spring fog or an autumn haze holds the temperature at or near freezing. We guess that during the 120 days from April 1 to June 10 and from August 25 to October 15, our garden may have around five killing frosts and another dozen mornings with white frosts on garden paths. Any one of the killing frosts will eliminate or cripple sensitive seedlings. All of the near-frost nights will retard germination and growth.

A can, bottle, box, or basket — or even some newspaper or a light mulch — over each exposed plant will tend to reduce the frost damage, but a greenhouse provides exactly the needed protection for everything inside its four walls. If we have perhaps 105 frost-free days and another 120 days during which a bit of glass will ward off frost damage, an unheated greenhouse in our climate belt will provide adequate frost protection for at least 32 weeks of the 52-week year.

Greenhouses Allow a Variety of Plants to Grow

Our year-round greenhouse continually contains a wide variety of plants; some more hardy, some less. In it at each season — spring, summer, autumn, winter — there are plants in various stages of development. Seeds, tiny seedlings, or mature plants occupy every square foot of the greenhouse. Some seeds, recently sowed, are not yet germinated. Some will make the salad for the day's evening meal. Some, like tomatoes or peppers, remain in the greenhouse for months. All these plants, in various stages, will be transplanted, consumed, and replaced in their turn. Before the greenhouse soil gets its next crop of plants or seeds, it will be reworked, refertilized, and either reseeded or occupied by seedlings raised in another section of the greenhouse, and reset in the recently vacated soil.

Each month and season will find some variety of plant life playing its allocated role in providing the edibles that make up our daily diet. The sequences are carefully planned to produce the maximum in food value from each square foot of greenhouse soil, and all tend to extend the growing season.

Winter Garden Hazard: Cold Weather

New England wintertime has usually been ruled out as ungardenable unless it is undertaken in artificially heated glass houses. Our greenhouse is unheated save by direct and indirect rays from the sun. Nevertheless we eat out of our sun-heated greenhouse right through the roughest and toughest winters. How do we do it? We have learned how to live with and prevail against winter's hazards.

The first hazard, of course, is the cold weather. Where we live in eastern Maine, along the coast, the normal winter thermometer goes below zero many times each year. Most of our plants left in the garden crumple up and rot after a hard frost. Other plants, after freezing, thaw out time after time. The first task of the would-be winter greenhouser is to find out which plants will and which will not stand hard freezing. We have been studying this matter for the last forty years and are glad to share our findings.

Winter Garden Hazard: Snow and Ice

The second hazard is snow and ice. Snowfall may be a problem in its own right; it is certainly an effective check on gardening. Its after-effects may be even more serious. A New England snowstorm, driving in from the northeast, may include rain which melts part of the snow. If the storm ends by a wind shift into the north, the resulting drop in temperature turns slush and snow into a treacherous ice sheet that covers trees, highways, gardens, and footpaths. Work in the open is brought to a halt, with foot passengers and drivers alike picking their way with care, or calling it a time to hibernate.

Equipped with a glass roof, a greenhouse is especially hampered by snow and ice. A snowstorm cuts off light; it also adds to the roof load. If the snow is freezing as it falls, it hardens onto the greenhouse roof and stays there until it is softened up eventually by higher temperatures. We aim to keep the greenhouse roof clear of snow. We have a wooden snow-pusher with a long, light handle. As soon as snow has had a chance to soften up on the roof we push it off and let in the light.

Winter Garden Hazard: Frozen Ground and Freezes

A third winter hazard is ground frozen so hard that it cannot be worked in the unheated greenhouse. This situation is avoided or postponed by sprinkling, before the ground hardens, a moderate layer of dry autumn leaves over any greenhouse earth that is not covered by foliage. A little experience will show how thick the layer of dry leaves should be. We know that if lettuce and other such plants have a light mulch of dry autumn leaves thrown on them it helps them to survive. Even on a sub-zero night the ground covered by such a mulch may be unfrozen.

We have checked this point on a bit of land covered by a thick growth of soft maple, white birch, and pin cherry. If the normal leaf cover on such a piece of woodland is undisturbed there will be two or three inches of dry leaves that can be kicked aside, revealing an unfrozen forest floor. Unless the ground is water-soaked, the leaves have curled up and are able to keep large air spaces between leaves . . . which prevent the ground from freezing.

If any of the soil in the cultivated area of the greenhouse is exposed, keep it stirred up with a light stick or a small tool, even when it looks as dry as dust. Really dry ground cannot freeze; it is the water in the ground that freezes.

Another hazard is the succession of freezings and thawings that the plants may have to undergo in an unheated greenhouse. One or two such experiences may not prove fatal, but too many might finish off delicate plants. The foliage of most hardy or semi-hardy plants will survive a great deal of freezing and thawing unless there are juicy stems or other exposed parts that get iced up. Deal with this difficulty by not touching frozen, brittle plants that may break off before they thaw.

Growing Wintertime Lettuce

We come now to lettuce, which is very important to us because we use it so frequently in salad making, and go out of our way to have this tender fresh green for at least one meal every day.

Lettuce is a rather fussy cold weather plant. During a zero night the entire lettuce plant is frozen stiff. When the sun thaws out the plants, those with thin leaf stems continue green and alive and go on living normally. After several freezings, lettuce with thick leaf stems begins to rot. The leaf stems in Oak Leaf lettuce, for example, are relatively thin. The stems of Simpson lettuce also are thin; the leaf stems of Romaine are juicy. The Butterhead lettuces generally have moderately thick leaf stems.

As our experiments have proceeded we have found that Simpson, Oak Leaf, Green Boston, Buttercrunch, and other lettuces with particularly dry leaf spines have survived during our Maine winters. With one exception (the winter of 1975-1976) we have succeeded in carrying some — at least — of our lettuce plants through every winter. Almost always they went into winter as half-grown plants or even as plants still in garden flats.

Our lettuce plants still in shallow garden flats were wiped out the winter of 1976-1977, while those in beds survived. Weathermen counted ten distinct storm cycles from the middle of November 1976 to the end of February 1977. These storms followed one another closely, without a single thaw break. In the severest weather the curly endive and escarole were retarded but did not die. Their growth was checked but they were not killed by weeks and months of sub-zero frost.

Growing Escarole in Winter

We would like to refer especially to a bed of broad-leafed Batavian escarole which we raised in a seed flat and then transferred to a garden flat. They were three inches high when moved into a greenhouse bed and covered with autumn leaves. All of these plants survived the same winter that killed the lettuce which was in flats.

As we pass this unusually persistent and prolonged winter season in review, we are pleased we went through it before we wrote this book. Despite its extreme severity we can report that we were able to carry a variety of vegetable greens through one sub-zero period after another with no thaw in between. Each sub-zero cycle proved to us that our basic assumption concerning the capacity of succulent green vegetation to outlast deep freeze is established beyond question.

Our Fragile Winter Celery

At the other end of the equation is the recognition of the unquestioned fact that all growing things have their limits. Celery is more fragile than lettuce. Its leaf stems are thick and juicy. In the winter of 1976-1977 we had a bed of celery plants which we had raised from seed, put into garden flats, and heeled into the greenhouse in the autumn of 1976. The celery plants took the transplanting well and went into the winter lightly mulched. We then entered into the toughest winter in memory. In the course of that winter this batch of celery was completely wiped out, but it survived for more than a month with outside temperatures down to seven degrees below zero . . . and up to that time showed little frost damage.

Not all Plants Will Survive

It is obvious that all vegetables will not survive a winter in our sun-heated greenhouse. We selected hardy plants and treated them as well as we could, and we learned a great deal during these experiments. We found out that a homesteading family using a sun-heated greenhouse as its medium can supply itself on a twelve-month basis with salad and other greens taken directly from the garden and greenhouse. If our contention is upheld by subsequent tests, New Englanders and other cold climate homesteaders have a means of greatly improving their winter diets without dependence on artificial heating or on products imported from Florida, Texas, California, or Cuba.

Winter Parsley Has a Good Chance to Survive

Meanwhile we are continuing our experiments with a greater variety of plants because we would like to have at least a dozen greens that will survive the Maine winter in a sun-heated greenhouse. Our guess is that much depends upon the water content of succulent leaf stems, also on the moisture content of the soil in which the plants are growing.

We know that a parsley leaf with a juicy stem will freeze, that the cells will burst, and that with the first warm weather the stem will begin to rot. But please note the difference between the stem and the leaf webbing. The leaf web may go on living for days and weeks despite the loss of the leaf stem support. This fact leads us to conclude that certain varieties of parsley, lettuce, and other plants- carefully selected for the relative dryness of the leaf stems-will survive, particularly if watering is reduced to a minimum.

The Nearings: Living a Better Life

Through the ages human beings have been searching for a good life . . . a better life. The current movement to homestead, to live simply and quietly, in good health, in clean air, and in the country is part and parcel of that long-term trend. It is not only a movement for individual betterment; it implies social change and improvement as well.

As the determination to live a better life spreads through the North Temperate Zone, it is being transformed from a wish or dream stage into concrete social patterns. Providing fresh green food in a sun-heated greenhouse is but one example of this advance. A large degree of self-sufficiency lies within the easy reach of any homesteaders who have established themselves and who are ready to put time, energy, and ingenuity into stabilizing their homestead way of life.

A sun-heated greenhouse is a project that practically any family can work at and benefit by. The undertaking can enlarge the possibilities of income. It can extend and enlarge the variety and quality of food consumed. It can enhance the homestead itself by an attractive addition to the home buildings. And it can open up a better life for its builders and for the country at large.

From Building and Using Our Heated Greenhouse by Helen and Scott Nearing, copyright© 1977 by Garden Way Publishing, Charlotte, VT, and reprinted here by permission. This book is available in hard cover ($9.95) and paperback ($6.95) from any good bookstore and (in paperback only) from MOTHER's Bookshelf.