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FINAL SCOREsides then resting thepare it to that of a typical above-ground greenhouse of simi-Which means it would no longer be a grow-hole now but"I didn't have either electricity or a place with central heat

HereCompare the two systems in their relationship to the airditional -20% is probably quite small, we are going to use itbe braced from the inside of the structure. This is a hassleCorrect tamping is an acquired skill and the most misun-angles to each other so that they form four sides and a topversion - had just dugHere's the story of what I fmally achieved near the Ca-decomposition of the fresh horse manure.This greenhouse had the additional benefit of the earththis, and it is this simple: The coldest air, which would sink

- say if you wanted to leave some of the seedlings in the pitsquare foot example only to stun you into realization of howaround the post. We tape them in several places and take carethis has you confused, skip over it. We're merely trying to bening across the bole and packing loose dirt around the edges.the posts at all and tbey, of course, rotted out and had to bepany executives and other rascals may protest that a lengthy 20-and it is warmed passively by the heat of the earth . ThisIn the case of the grow hole the ratio is reversed. Theon? I watched with alarmed fascination as the rate of descentand no longer were willing to use that poisonwould be, in fact, a greenhouse.21cause in a 20' hoop row there is only one square foot of above-glazed by simply laying a window down on the ground span-tions. When the concrete set, we removed theMore problems: We still have the shade factor causedmilled trees, the easiest way we ' ve found to check plumb is byMy second improvement came wben it became obviousfice. We have taken care before charring to make sure to cutThis was back in the early ' 70s, now, and memory dims, but

required either longer and wider glazing or smaller grow spacewas going to be filled up with horse manure and growing soildeveloped when we built my original $50 underground house,later read that if the degree is great enough from perpendicu-branch of Scotland's famed Findhom community in the earlyand mentors they smi led ruefully and shook their heads.would be soon in mywas 5' high x8' wide, giving us an additional +40 heat units,The Earth-Sheltered Solar Greenhouse Bookpenta and diesel oil solution. When we came to our sensescover long rows of plants, for the sake of illustration let's cre-

Subtract a +40 for the heat arising from tbe earthen floor, and wepitcb tbe roof, we would get 202' of exposed surface for a -202.lated here has glazing on the east and west walls, totaling


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H18add another negative unit to that method, making it -6/+ 1.donnant January garden a volunteer crop of green and ediblefaces combined, or an additional minus 20% for each of the27

+40the four sides and top each have an area of one square foot andgone through the looking glass with Alice? What was goingseason a couple of weeks at best. Many hours of conscien-might wish to keep36 The first cold sink greenhouseas in the illustration. To avoid this, the post mustthat J would need to shore up a grow-bole if I was going to im-area. Clearly, I was going to have to shore everything up.House - whicb was an addition whicb tripled the original tinyabove-ground walls each had 8 sq. ft of glazing for a -16.

the plants. That may have been the year that I saw one of myground buildersbad built the economyof the sun and the warmth of the earth. How I pondered and-242 units -91 unitsout siding it off with anything - figuring that the lower portionown creosote, for creosote, we are told, is the product of thewarmer throughout the night and during cold days than is that ofholes must be large enough to accommodate shovel handles allwill add 25 per cent more heat per square foot than the other. So

j- blocking at least half of the sun - and I was spending pre-been protected from the earth in some way into the ground,backfilling and tamping, but stopping to check every so often20cates of the above-ground systems. We gave you that onethere is the fact that since the grow-hole is sunken it is downtwo house roof layers, however, we are now beginning to useThe Earth-Sheltered Solar Greenhouse Book 23Tne Earth-Sheltered Solar Greenhouse Book 35And there was a -2 for that vent we mentioned. All together,

greenhouses four-season successes. The cold-sink concept isedges which may rip the polyethylene. We have previouslymoderates somewhat the effect of excessive heatEPDM, the artificial rubber swimming pool and containmentmoist sand. Radishes, too, I discovered, would keep in moistgrow-hole.the second person standing back and sighting down a plumbincreased till the entire plant disappeared into the earth! I wasThe Earth-Sheltered Solar Greenhouse Book 31this from two directions, say the north and east. When the guypoly with several inches of earth. That could tum those

house gets an additional -15 wind scrubbing units for a total ofrays tended to glance off like a rock skipping over water. Ithis first experiment, but these will be close enough: the


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as described in The $50 & Up Underground House Book.Above ground Earth-sheltereddles.We have progressed througb a number of methods foring the sun's warmtb at any given moment of sunsbine, weare

Post/ShoringfPolyetbylene, or P/SfP, is the method wethe strings and will just barely touch them. The holes, then,anyway.with a twelve-month fresh harvest. Simultaneously I wasby the low pitch of the sun blocked by depth of the south wall.bing". Wind scrubbing is what causes the "chill factor"No, they weren't eat-can make a day with a thirty-degree temperature seeminto wood. We were told it was a common practice amongwas lucky and the snow melts, he can sometimes find in his2' to)' in the ground, earth might be added six to twelve sepa-

dried strawbeny leaves. These brew into a beverage sothick. In our construction we generally use material that is 6 tobrought in for testing - till the lab technicians went out andbas over the grow-hole. The hoops have tbeir place. Elliottthrough the course of a night or cold spell, and we're talkingThe seedlings were taking a beating each time this hap-have to work lying down or sitting bent forward. But if you~when backfilling. A number of other implements may be usednips turnips, onions, garlic, squash, and pumpkins, tbougbthought to be salting with ascorbic acid the samples bebegan using the grow--11+5 unit situation.they were no longer heating with wood. This informationhad pulled up months before and hung upside down by itsreinforced with chicken wire and Y. inch rebarbegins the backfilling. Because of the irregular surface of un-would move the glazing a foot or two away from the growcauses, I think: the fact that I don 't have a green thumb; that Isouth wall in the shaded area to stand in while working on thegrowing space for

Now I'm not a mathematician or a scientist, and this isproved upon. One was the pitch of tbe glazing. If you are los-10 mil. thick - excepting when we use multiple garbage bagsHground will be losing heat while the growing surface belowbob string visually aligned with the edge of the post. We doing the plants as tbeygrow bed was 3'x8' for 24 sq. ft. The floor of the cold-sinkslipped the post down over the rebar via a 'I.-inchtime. Other problems, design problems, began presentingstaked out the site with batter boards, and run string to inform

What we came up with in the end,of most of theis 318 heat units to the better compared to a similar above-


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$&1 gophers were happy.ground for tbe earthwild winter cress. And you can count on wild dandelionthe way around because we usually tamp with shovel handlessun was shining and the air reeked of the polyethylene disinte-

use three 2x6's nailed or screwed togethertending the growing season .We call itpoured concrete footings.than four hundred dollars I was able to permanently triple myfirst killer cold, then finding that I was only extending tbe25keeps it from stacking back up and covering the plants again.we had one that was 5'x8 ' with 6' walls witb a one-foot rise towhere there is a need to temporarily shelter long rows of crops.house over the loss ofa still-air night. Ne'er-do-wells, oil com-

the above-ground system.But where were the fresb winter greens? A prettythem lip on concrete piers that we had previouslythe danger of frost has passed. [t can thus extend the growingtotal plus of 32 more units to the earth-sheltered green-,Iearth behind the wall pushes in hard enough toThe Earth-Sheltered Solar Greenhouse Book 41mile-per-hour wind for any length of time on a 25-degree nightnegative units on the hoop method, incidentally, when com-for a greenhouse catastrophe. Now despite the fact that the ad-clude that a grow-hole is up to eight times more effective thanthe advantages ofThe first cold-sink greenhousetunnel with no care whatsoever about where it went, because itous about such glazing in northern climates. In manyboxes or bins up off the ground and the carrots in pails offair and objective here, and to try to head off protests by advo-would find yourself cramped by the low glazing there. You'dhaps 6 to 8 inch depth then compacted to perhaps half that be-in humans and animals on cold, windy days. It is what

prove the pitch this way. Vague memory recalls that tbe sec-..:i!.t -concept is a tale in itself. So that you may have year ' round4. Similarly, a grow hole traps, utilizes and stores muchhouse projects the smaller, white garbage pail liners might suf-I. It is down out-42Then we wrap the cooled, charred ends in plastic gar-make my land payments to weed and water properly; that thethe principle upon which this book is based.begin to shake when none others were. Was it the wind? Then

camping at first), and a grow-hole made a lot of sense as a waycorrect it, or at leastI had met the enemy and he was #%$&! gophers.


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doing the reading is satisfied with the plumb, he begins thel"![picked their own leaves to test.So that's what I built. 1 didn' t realize at the time that I'dstring beans, corn, pickled beets, peppers and, of course, the38 The fi rst co ld sink greenhouse

A second problem quickly manifested itself: the sides17incomplete combustion of wood. Not many critters, mi-ground greenhouse.In the original $50 Underground House we hadn't protectedbedded longer, perhaps for the season. So that was my firstplant, say a tomato start, under protection. Let's say he insertsground. We use small trees right off theSboring would solve the #@%$&! gopher earth dump-sbould add a final two plusses, bringing the score to -1 /+ I0 vs.structure in an excavation and, before backfilling, you protect

A person would not be far off, probably, were he to con-growing surface adding heat is joined by the four walls alsobe the first of decades of struggle with those #@%$&! demons.a two-step process. The first step is to charI discovered the winter pleasure of borne canned peas,-6/+ 1.for tamping of course - as long as they do not have sharpseedlings and sometimes mature plants. This is when garden-than a century. A grow-hole consists of a pit two to three feethole as a dumping;~Finally, you had to open the grow-hole to work on theand not always feasible, so we continued to search for otherafter the charring. We char them over ar did and it worked. I put the potatoes in sacks or inGREENHOUSE: - 202 HEAT UNlTSthe ground. I stood there, mouth agape. I began to questionfrom the excavation which we piled behind the north wall.pared to our own one square foot example above. This is be-the grow-hole so we can add another plus unit there. ThenCHAPTER 4

43wonders of cucumbers turned into diU pickles. Friends tuned;1----',- ,earth is pressed against it during backfill. Then we dig holesto the otherwise lowest spot, the growing bed, now spills intowith either posthole diggers or shovels and set the posts. TheNo doubt many of the old-time farmers used storm windows46 P(SfP constructionThe grow-hole conceptout of most of the wind avoids most of the wind scrub-If we call each heat-losing square foot a minus one unit and

minus 2 for a vent. That would be 38, then. The east andNone of the others were quaking . I stood and pondered thisCOLD-SINK GREENHOUSE


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(l0'x I2 ') $50 Underground House - we soaked the posts in aheadache and requested another assignment.) And there isground greenhouses, and [ saw this used in a greenhouse at awhen wrapped with clear polyethylene glazing. Let's say thatSetting these posts is pretty much a two-person opera-5. By storing heat in the surrounding earth, a grow-hole

The fi rst cold sink greenhouseplanted seedlings were spindly, and that the plants I left in togan a personal quest to find a passive, low-cost way of ex-adding heat. Since there is only one unit losing heat, it is apond liner.since, for the glazing to have a reasonable pitcb, it would havenot all of these are root cellar material.my sanity. I was just a couple of years up from my Californiaimprove upon it? That40 The first cold sink greenhouseshould be as simple as

What I finally decided was to dig a trencb along thepea plants, waist high in a row of similar plants in my garden,roots in her family's root cellar. Not prime stuff to be sure,protecting tbe posts where they are in contact with the earth.strong in natural vitamin C tbat autbor Ewell Gibbons wastraditionalCHAPTERSfor reason of comparison factors we have to add +41 morebegan (a) immediately crumbling into the grow area and (b)can 't remember all the details, but I do recall that my trans-whicb extended four inches out the top. Weground. This is another old-time farmerand plastic system, a common method today of protectinghole traps, utilizes and stores the heat generated by thecampfire till they have an eighth to a quar-mature did not produce and, in fact, did not survive. The for-32use it on both the walls and roof of our houses. For one of thecases we think the better move is to berm earth out there,Let's go back to our beat unit method to calculate thenot sink the posts into tbe earth at all, but to set

stumbled into the earth-sheltered greenhouse and cold-sinkvs. hoop and plastic method we gave a -I unit for the five sur-Chapter 22. There is littleThe rest of the minus units? Well, there was the southI did not repeat my grow hole experiment the next year.efficiency of tbis earth-sheltered, solar greenhouse and com-rate times during the post-setting process. If large amounts ofwas going to invest such time and resources, then wouldn't ithouse, raising its score to + 148 and the comparison finalnique that had been used by farmers in cold country for more

Among several other advantages, this eliminates the need for+40 units +207 unitsat a time, pulling the surplus to the sides, then wrapping it


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was supposedly related in one of the Foxflfe books, but totious gardening work deserved more reward than that. [be-'L_--;,:the north and slanted on the east and west sides and that, sincebeautifully. Otbers were having success keeping beets, pars-Let's compare for a minute grow holes with the hoop

able to drastically cut down loss from predators. This was alland on a slant on thepoured in greased 6-inch or 8-inch stove pipe sec-The grow-hole was not a success for me that year. IColeman has had good effect using them inside his abovederstood part of post setting. The earth to be backfilled andscore to a win of + 350.One supposed old-time method we were told about in-of the cold-sink was a door and was a -10.methods of post preservation.one square foot example above the ratio was 2/3 or 40/60. If

years in a row I'd scurried along, same as my gardeningshaded area against the south wall - the logical place - youplants which wereeach heat-adding a plus one unit, we see we have a -5/+ I unit30 The grow.ho]e in practiceple slices.model. It would be a super deluxe grow-bole. And if a guyceiving too much shade from the walls. The latter had manygarden. Instead, they26be able to report my roaring success, but, alas, that is not theWhen the sun goes down, the five surfaces rearing abovedeep in which the bottom six to twelve inches has been back-hippy days. Cold this be an acid flashback? Had I suddenlysun when it was low in the sky and in the morning and eve-method, we did some experimenting. One was toimprovement.for this. They' d be taking them off the house in the springwarm and it is important to understand why, for it illustrates"astounded me by making coleslaw from garden cabbage she

Sun low in the sky presented another problem: sincethe earth. It radiates up, warming both the soil aroundThe Earth-Sheltered Solar Greenhouse Book 19themselves. One was that the depth of the walls shaded the22 The grow-hole conceptthe roots and the trapped air in the space above.A growGophers and my poor results aside, there were a couple ofstumbled upon the "cold-sink" concept which was to make myhold it with one hand while scraping in the earth with a shovelyou'd be taking up prime growing space. That way you'd bethemselves. Polyethylene comes in rolls of various sizes. We

utility on factory farms, where tractors do the cultivating andthe dormant winter season - a nine-month growing seasonabout five surfaces - add another two plus units. And, finally,


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the loose earth wouldn ' t of its own stand in vertical walls, itsky towards summer, there would still be no sun there duringkind of a trapped bubble that could pop the poly when thecious time blowing and shaking and washing off as mucb as IA grow-hole allows you to plant garden plants a monthAnd there is the wind scrubbing factor. This is a toughie

covering my seedlings and throwing the earth out of the grow-the two. The soutb wall, the cold- sink wall, was 5' x8' for awould be considerably larger. It would be a "structure". Itmonths of tbe year instead of one to three months? I wasning. Score one for the hoop and plastic method.Note: The earth-sheltered, cold-sink greenhouse calcu-the months when it would be most beneficial.pay to solve some of the other problems at the same time?tion. One holds the post while the other sees ifit is plumb andneighbors, to cover tbe tomato plants at nigbt in dread of thegreenhouse, being below ground level, is going to be appreciably

piling tbe dirt from themethod of fence post preservation. Char-land for the posts and peel them first.hole, doing much of the gopher's work for them.replaced after ten or twelve years. In the $500 Undergroundtaller and that you+24, while its west wall was 2'x5' for a + 10. The east walladding heat or +40 energy units. The back, or north, wallwest walls of the growing bed were each 2 ' x3 ' or a + 12 foryoung Seventb Day Adventist cook in my favorite restaurantfive -I units. That is probably quite low. Seems to me a 20-TRADITIONAL ABOVE GROUNDgetting tired of seeing my hard work go up in frost. Severalbut still edible and organically grown. I learned that if a guybing.ring hardens the wood. [t also creates itsers and farmers straddle the plants with hoops stuck in theWhen I described this phenomenon later to my friendsto start a garden early. So of course I made one.less than that. I did not repeat the experiment a second year.place by the roots of the grass surrounding the pit. It sounded

ing problem, too. But it would no longer be the economygood in theory. But the end result was the gophers discoveredopening the hole to work on them? If you were to avoid that,The long rows do cut down proportionately on some of thebuildings and above-ground greenhouses also. Beingthe other which is on the surface. A reasonable guess is tbat itworked against the north wall where there was head room,anyway, thereby squashing the hysteria of critics. We add an-now, is what could be called the "Charithe glass was horizontal to the ground, much of the sun'swhy weren't any of the other plants shaking? Earthquake?

the protected growing surface beneath is also one square foot.That means that this simple, earth-sheltered greenhouseThe grow-hole in practice


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ing soil, and the top foot is growing space for plants. It isthen notch girders into them for floor joists and rafters.units, making it now +207 minus -76.sand. Apples, if they are "keeper apples", will over-wintercould easily double the heat loss from an above-ground green--32

organic greens for pennies, and need not reinvent the wheel,hole drilled in the post bottom. This is the methodcould be up to l4 times more effective in sheltering plants thanIt would be nice after that big build-up for grow-boles towill be radiating heat from the earth's depths plus the suo'smade indoor starts practical, it was a real boon to the gardener./.:r--us of the outside boundary. That is, our posts will be set insideto keep squeezing the air out of the bags so not to have anyfriends told me about the grow-hole concept. This is a tech-Not only did it eliminate any wind scrubbing against that

theless.was 2'x8' or an additional 16 sq. ft for a total of 40 horizon-things about the concept that looked like they could be im-,then, this first earth-sheltered greenhouse had a score ofll last most all winter.",me on to beef and venison jerky, and gave me home dried ap-face, wbich was a glazed 8'x6' for a -48 . The east and westcome up with -162 heat units.earth are dumped at once, it will not tamp solid all the wayter-inch of charcoal over all the area that isies and successes one by one. And I'll tell you how you (andP/S/P constructiontrapped on sunny days.not a million-dollar researcb study, but it would seem to me aseason a month or more. Before electricity and central heat28 The grow.hole in practicemust stretch beyond the string to acco=odate the shovel han-3. A grow-bole utilizes the heat stored in the depths ofcase: It was only moderately successful at best, maybe even

of what under-to see if the plumb is off. If a person is using milled lumber,all right as far as it goes, but, trouble is, it does not go very far.And we have forgotten that the horse manure is adding beat toexcavation to tbe northThe Eanh-Shellcred Solar Greenhouse Book 29push both the post and pier into the structure a bit,polyethylene. We use five bags as a rule, but put them on oneHow would a conventional 40 sq. ft greenhouse score? IfPolyethylene is the stuff your plastic garbage bags are"hinging". This is when the pressure from the

advantages which we will mention soon that the hoop metboddid begin to crumble and they began leaving gaps around thepened, of course. Their leaves were coated with dust and mud


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The Earth-Sheltered Solar Greenhouse Book 37greenhouse by night.I) can have even more grati fying successes in the future.tamped around the post must go in small increments, of per-.\find it.

losing growing space against both of those walls.+ 164 and -76 heat units. That's 88 heat units to the plus.two hoops into the ground a little more than a foot high at rightlike ten degrees. What that wind does to you it does toThough tbis problem would lessen as the sun elevated in thewould also give moreond year I actually got a new bole dug and the earth piled toother additional -40 units to the -202 for a total of -242 thenwall, but now it became a heat sink in its own right. [t wasplants. This shocked the seedlings on cold days. No way toate a situation in which a grower might want to put a single

crobes included, want to eat creosote-laced charcoal.anyway, and the top foot of earthen walls would be held incall "wind scrub-33the end of the post that is to go into thestorm window used as glazing. I patched as best as I couldtheface. They could instead just shove it horizontally out theirAnd there was thc problem of just where a guy was tosince there is five times more surface area receiving and stor-insulate it, cover the insulation with polyethylene and theeffect of wind scrubbing on the hoop unit so we can probablyThose were problems due to lack of materials andmade of, only garbage bags are usually just 1.2 millimeterA grow-hole is far more efficient at keeping the seedlingsfore the next course is scraped or shoveled in. On a post sunkwind.factored in. The first is that the earth in our eartb-shelteredMy quest to extend the growing season began whenthose early years (all right, I didn't have a place at all - I waswas pretty new to gardening; that I was too busy working to

The concept is simple: you construct a post and beamstove pipe for the next pouring. The concrete wasThen there was the problem of what would happen ifof the heat from the sun 's rays.The coldest air is removed from the plants passively,the factors, but think also the #%@&! gophers finally foundCOLD-SINK GREENHOUSE: +116 HEAT UNlTSgreens fresh from the garden nine or ten or even twelveraI se your young.filled with fresh horse manure, the middle is a layer of grow-WINS BY 318 HEAT UNITS

plants. That way I would have headroom. And with a growphenomenon till I saw that the plant was beginning to sink intoThe pier method bas a built-in flaw whicb


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ing significant growth rays because of the pitch, then why notfrom their tunnels. IThe Eanh-Sheltered Solar Greenhouse Book 39layer of polyethylene.the roots of the plants reached the fresh horse manure belowends into heat sinks and give a + 16 instead of a -16 for a

-91 units. The fmal math then reads like this:Where these are not available, a guy couldto go two to two-and-a-half feet into thevolved soaking or otherwise impregnating stovepipe creosotewe anticipated from the start.our disappointment we were never able total square feet. That's 40 square feet of horizontal surfaceor so early for subsequent transplanting into the garden whenground over which they stretch polyethylene. This system isI' ll take you through my thought process, fumbles, di scover-24 The grow-hole concept

1980's. (In fact [ was put to work in that greenhouse when theand what we are using on our structures...,.", .to guesstimate. During the discussion before of the grow-holethe hoop and plastic method. But wait. We have forgotten themile-per-hour wind is rare and might only happen once in awe used on the hillside greenhouse.A grow hole looks like this:the lumber siding (shoring) from the damp of the earth with a(x2)bed just three foot across, soutb to north, I could work all thefor the above-ground greenhouse. Our earth-sheltered green-with boards and earth, but cold air was seeping through none-winter - but once is enough. The plants need only freeze oncewhere the earth has lost a lot less heat than tbat on the surfacePost and beam itself is simple. You set posts that havecould, and neitber the plants nor I were happy. Only the #@%off any sharp edges or protruding limb stubs that could tear thesituation..,'+40 units. The nortb wall of the heat sink was 3'x8' for a

34lem with the hoop method - score another.)bage bags, usually the full-sized black ones, though for green-you'd have to work the plants from inside the structure.and the earth. Though the hoop system is generally used toThe Ean h-Shcltercd Solnr Greenhouse Book 45greens in the spring before you can even think of workingLike how about the problem of chilling the plants whenmiserably folks have failed to appreciate earth sheltering .tem that has worked well for us so far. It'sthe trench where it is warmed by the earth behind the walls.

Tbis is not to knock the hoop system. There are a fewProlog to a happy discoverying. Wouldn't that bum the plants?


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here is what I recall:to grow after transplanting. Or if you were late in transplant-plants by just reaching. I would never have to get up in theguy migbt speculate reasonably that the sunken grow-holeCHAPTER 3to rest on tbe highest part of the mound to the north. That

position himself to work on the plants. If you utilized thein the other, inverting it and tamping with the handle."Gophers," they said.was not going to faU back in. The result was [ was daily un-achieved without any energy other than my labor, the warmththey no longer had to shove the earth uphill and out on the sur-lar you can lose up to 95% of the rays. (This is not a prob-grating from the ultraviolet rays. Within a half hour 1 had afarmers for their fence posts, and they only stopped whenwarmed by the sun all day and radiated the heat back into thesay 6x6s, he might be able to tape two levels to the post and

nadian border in a North Idaho mountain valley. For lessBut again there are two more considerations that must beground surface area on each end proportionate to the 60 sq. ftgarden soil. There were other tricks like making tea fromAlmost immediately I had gopher problems. This was toa three-foot hole with--202 units +1 16 unitsminus 16 units. We'll see in Chapter 16 that we are dubi-roots probably reached the manure. I think those were some ofBut wouldn't it be nice to have home-grown, organicheat which has been absorbed near the surface during the day...42lar floor space. I can ' t remember the exact measurements ofmer was doubtless the result of being buried often and also re-growing bed at all.down. Poorly-set fence postsof surface area on the two sides and top, or a 2/60 ratio. Ln our":...------glazing on it. Thisgarbage bag system" - not an intriguing ti-

growing season. I was also able to harvest some greens instunned.44 P/S!P constructiontle perhaps, but a descriptive one for a sys-

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