Last winter I followed advice in Elliot Coleman's book (Winter harvest handbook) and had great luck in *harvesting* fresh vegetables all winter. They did most of their growing however in the fall (I started them all in late September or later) and then later in the very early spring as in the winter months they barely grew (although they did a tiny bit). My set up: Hoop house - It was an existing (built by me and my husband a handful of years ago for season extention) 12x16 plastic covered hoop house. We made it out of plastic conduit and the only thing we modified for the winter is that we swapped out the flat 4 way fittings at the roof peak with adjustable angle fittings. I found that 45 or 90 degree fittings didn't work (too sharp an angle) and I didn't want to not have an angle for the snow load so I went with manually setting the angle as steep as I could with the adjustable ones. (You can find them by googling "PVC 1" Adjustable Ell Fitting 3 Way" or "4 way"). We never removed snow off the top of it - By design or by luck the snow would shed off the side. (Although I hear brooming it off is good practice.) I sealed the window and door with weatherstripping. I also added ~ 800 gals of water - some large tanks (which were a royal pain to get in) and lots of single gallon containers. against the north wall. I also added 1" foam insulation along the north wall - including covering 1/2 the "ceiling" on the north side (taped to the conduit frame in some areas). I dug the foam insulation ~ 6" deep around the perimeter. I then planted in two 18" rows separated by a small 1ft step path - all under a 4ft wide floating row cover (the row cover hovered on smaller plastic conduit hoops). Under the row cover in the small 1ft step path I put as many gallon jugs as fit leaving me with step spaces. I also put a few 1L and 2L bottles on the outside edges under the row cover. I also put one strand of old-fashioned (ie not LED) christmas lights suspended from the conduit as my "emergency" heat source. I put my thermostat for my lights outside my row cover and set it to turn on at 28*. I also grew a few earthboxes full of veggies but I found that anything in a box didn't grow nearly as well as things in the ground. I think the roots get too cold and they stop growing much, much earlier (but they didn't die - just didn't grow as much) even though they were under the same row cover but they didn't die. The last thing I did was put a small muffin fan attached to a tiny solar panel under the row cover for air circulation. I had my window/door always closed (ie I disconnected my autovents) for the winter months (Dec-Mar). I also never went in to harvest except during the day (almost always a sunny day) when opening my row covers wouldn't release any trapped heat that was vital for the night. I weighed down one side of the row cover with cylindrical bags of sand that I could easily remove and then the other side with soil/rocks piled on top. Watering was mostly a non-issue, but I'd carry in my water in jugs on sunny days and water by hand. I think I had to do this maybe 3-5 times all winter (ie monthly). With this set up I successfully grew: kale, leaf lettuce, carrots, beats, chard, mache VIT, bok choi, spinach, etc. For most plants I would harvest outter leaves and leave the inner leaves to continue growing. With that set-up each plant continued to provide until the late spring heat caused them to bolt (which was fine since I needed the space for the next round of crops). The temperature inside the row cover was much more stable than in the hoop house in general. The temp in the row cover never dropped under I think 25 - even after multiple cloudy/stormy days. In addition my hoop house is drafty so perhaps with a more sealed-tight environment no extra energy would be needed and/or maybe more ventilation. Oh and my hoop house is on the north side of my property and has mature trees ~ 50 feet away from it on the east side which did shade some in the morning (but not so bad because they didn't have leaves) and then we have evergreen trees that would shade the late day sun as well. I still think it's worthwhile but it depends on how much sun you get. I'm planning on building a "real" greenhouse (twinwall, etc) and am spending this winter scouting for the right location (best sun). I plan to use an earthen floor due to my experience of growing in pots vs in the ground, but am still doing my research for that as well. I've read that wherever possible you want to insulate in the ground to keep from losing heat that way. I plan to do that with my final greenhouse. Also wherever you are realize that both snow and a kneewall (if you have one) will shade part of your greenhouse floor in the winter due to the low sun angle so you may lose "significant" growing space that way.

Mike, in my post I said I did not use my lights to 'grow' plants, I said I use them to provide 'short night' response in my photoperiodic plants to postpone their bloom times. For that, I don't need 2K foot candles, I need 20 foot candles. For the purposes of determining the quantity of light your plant is actually getting you can't just spit out the wattage or lumen rating output of a bulb as rated on its package. For instance, a hundred watt, unshielded incandescent bulb, ten foot away from an object will only provide about 1.5 foot candles as measured at that objects surface. That isn't much, is it? So, you can't just say a lamp has X lumens and have that mean much of anything. That's the potential output of the bulb. What you are interested in are the readings at leaf level, measured in lux or light density and that is going to vary greatly depending on how far away the light source is, what design the reflectors are, angles, intensity at various points of the cone of the beam. Yadayadayada. And if you think you are actually doing much trying to supplement the natural light by hanging a few shop lamps from an overhead beam in a greenhouse with a flourescent tube in them............well, it's not going to hurt anything, but it probably has negligible actual benefit to the plant. So, if you are really needing to provide lighting by which a plant will actually grow.........then your supplemental growing light has to be quite close to the plant, or the output has to be considerably higher than you think if mounted from overhead beams. The only way to really tell is to meter it out at various points in a greenhouse. That's why I suggested the poster find out what intensity of illumination leafy veggies really take. If she/he can make do with natural light, it would save a lot of money, and I suspect they'll grow just fine without supplementation. That's why in all but special circumstances where high light levels are absolutely necessary for producing certain plants in a winter setting, most growers do not go the expense of installing supplemental lighting. It's expensive to install and it's expensive to run, unless you are just interested in starting a few seedlings or a very limited collection of conservatory plants.

Wow, I'm very excited I found this thread. I'm working on building a passive solar home. As of right now, we're still in the design stages but we look forward to getting started quite soon. I would love some opinions on our extreme building methods though! Initially, my wife and I had planned on building a Simple Survival Earthship, which is more or less a bare-bones solar home. But we recently came across some information that should accomplish the same thing, yet be way cheaper and quicker. I would love to hear what this group of experts think! The concept is a machine-compacted home. The Earthship design used tires as a form to hold dirt, which you would pack tight with a sledgehammer. The end result is a 3-foot thick thermal mass wall. This requires a good deal of tires, time, and chiropractic treatments. Instead, we would use a bullldozer to accomplish the same ends, in a much faster timeline. The walls will be similar to a pond/dam wall. Heavily compacted clay walls, track-rolled with a 3+ ton machine. Instead of months and months of pounding dirt into tires, it can be accomplished in an afternoon. After the walls have been compacted, the backhoe uses it's bucket to cut a straight vertical wall out of the compacted clay. The end result is a 5 foot thick compacted wall. On the interior and exterior of the wall, we would then plaster with a breathable plaster. This should eliminate any moisture issues. The floor of the structure will be a stained concrete. Also, the house will be aligned on an East/West access, facing south, with an attached solar greenhouse. The house's interior will be bisected lengthwise by some form of brick wall. The north side of the house will be devoted to the "cool" rooms (bedroom, bathroom, laundry) whereas the southern rooms will be devoted to the "hot" rooms (kitchen, living room, lounge). Adjacent to the home is going to be a heavily shaded, mulched, misted area which will act as our shade house. This shade house will provide cool air which we plan to draw into the home through cooling tubes (buried three feet down, running roughly sixty feet long, sloping downward into the home). The roof will be composed of metal (still deciding the details) which will be used to collect rainwater, stored in cisterns located amongst the shadehouse. All greywater will be recycled and divided between the greenhouse and the shadehouse plants. Half of the greenhouse will be devoted to relatively hardy tropical plants (bananas, etc.) and the other half will be used to house aquaponics systems. We plan to generate our electricity via solar panels. Question Time! The home itself is going to be bermed into a hill. Should I be concerned about below-ground water flows? Or should my compacted earth wall be sufficient? I haven't decided upon the materials of the central wall running the length of the home yet. It will most likely be a structural wall which will assist in holding up the roof. Should I go with cheap, concrete blocks filled with cement, and then cover with a brick veneer? Any other suggestions for a cheap, yet effect thermal mass wall? Any other ideas of how to get an effective, yet nice (pretty, non-crappy) wall. We plan on centralizing all of the plumbing along the west wall, located near the cistern set-up. To bring the plumbing to the outside and to transfer the cool air in, we've decided upon burying pipes into our compacted earth wall. Can anyone foresee any issues with that setup? We hope to move water in and out of the home via gravity. Any estimated costs on such a structure? We figure the actual earthworks will be no more expensive then say $3,000. After that's done we'll need to build the central wall and stick a roof on. From there the plaster will follow. The house will be roughly 1200 Square Feet, with enough overhang to shield the house from the summer sun. It will more or less be my experimental starter home. Any idea of a cost estimate to stick a roof on this thing? After the main structure is built, we will invest in the attached greenhouse followed by the shadehouse. I would love to hear everyone's opinions on such a structure. Has anyone heard of such a home being constructed? In theory it should work no different then an Earthship or passive solar home. Yet there is virtually no material out there using this kind of technique. I'm trying my best to foresee any possible traumas. If all goes well what we'll have is a "relatively" cheap, fireproof, tornado proof, self-sufficient, off-grid home. Although the initial investments will be huge, the long view of the houses expenses will be way minor compared to normal home upkeep costs.

Based on your screen name, I assume you're building in Texas. Unless you're way up in the panhandle somewhere - unlikely since you mention you have a lake place and there aren't many lakes up there (LOL!) - you're in an area where the number of degree-cooling-days per year is 2 to 2.5 times the number of degree-heating-days. Or, to put it more simply, you normally need to run you air conditioner 2 to 2.5 times as much as you do your heater! Be aware that much of what you will read regarding passive solar was written with cooler climates in mind. For those of us in hot dry or hot-humid climates, passive-solar must be far more about keeping excess heat OUT of the house (or moving it to unoccupied areas) than it is about using the sun's heat to warm our homes on a few cold days in the winter. So the very first rule is, you want to select windows with low solar-gain and low emissivity numbers. In colder climates they need high-solar gain glass. The low solar gain windows are sometimes called "Low E 2" windows so be sure you get the right kind. I love bright light-filled rooms and wanted every major room in our house to get light from two or three directions but I also didn't want to pay thru the nose to keep temperatures comfortable. So I did a lot of research on passive solar principles when designing my home. As a central Texan, I basically decided that, given that we can and do often have temperatures rising into the 80s in December and January and only very seldom have temperatures that drop much below freezing, it would be better for me to avoid daytime solar gain as much as possible pretty much YEAR ROUND. While we might have 20 or 30 days each winter when I'd want to have the sun help heat my house, we're just as likely to have 20 or 30 days each winter when excess heat from the windows could easily force me to have to turn on the AC. This meant putting most of my large windows on north facing walls. These windows provide plenty of natural light without direct solar heat gain. On east facing walls, you can have large windows if you have overhangs deep enough to begin shading them completely by around 9AM. Downstairs I have a wrap-around porch and trees that shade my large east-facing windows. I do have large unshaded east-facing windows upstairs in my master-bedroom and in one of the secondary bedrooms. In the summer I keep these windows covered with insulated window coverings that are opened for only a little while each morning as we get dressed. In the wintertime, I usually leave the drapes open to allow the sun to warm those rooms a bit because I know that even on the warmest winter days, by the time any heat really builds up, the sun will no longer be hitting those windows. On south facing walls, you should generally limit the number and size of windows and have deep overhangs that will shade them completely in the summer. Small windows set high on the walls with overhangs deep enough to keep them fully shaded in the summer but shallow enough to allow some direct sunlight to enter in the winter are best. But note that in hot climates - even in the wintertime, you DO NOT WANT direct sunlight entering a bunch of large windows. If you have too much unshaded south-facing glazing, your home will get too hot on those balmy winter days we enjoy. If you decide you must have large south-facing windows to take advantage of views, then put a deep covered porch on the south side as well so that, even in the winter, direct sunlight is blocked from all but a very small portion of your south-facing windows. I do have a bank of large south-facing windows in the breakfast nook of my home but they are almost 100% shaded year-round by a second floor deck and by a grove of nearby live-oaks which are green year-round. On the second floor, the only south-facing windows I have are in bathrooms and, in addition to double-paned, low E, low solar gain windows, they have glue-chip glass which cuts down on the solar gain even more. Total unshaded south-facing glazing in the winter is probably less than 3% of my square footage. And total unshaded south-facing glazing in the summer is as close to zero as I can make it. As for west-facing windows, in addition to large overhangs, I very deliberately positioned our two-story semi-detached garage on the west side of the house so that it almost totally shades the entire western facade from the setting sun. The three upstairs west-facing windows get direct sunlight for about an hour a day. The one west-facing window downstairs gets no direct sunlight at all. All four windows however receive reflected sunlight from the side of the garage for a good portion of every day so those rooms are all still nice and bright. (Reflected sunlight carries a lot less heat than direct sunlight.) BTW - even though both the walls and the roof are insulated, our garage stays toasty warm year round and in the summer can get downright hot...evidence of the heating due to west facing facade. The upper room over the garage was originally intended to be storage so we didn't bother to put in HVAC. It then turned into DH's man-cave but he uses it only when the guys come over watch football or play poker. On those occasions we use a couple of portable AC units to cool the place down. They're not terribly energy efficient but since used only occasionally, its better than paying to keep the whole space air-conditioned all the time. In addition to optimally sizing and placing your windows, the more "thermal mass" your building materials have the better. Thermal mass absorbs excess energy when it is warm outside and releases it slowly when it is cooler. Whether in a hot or cold climate, thermal mass helps to "even out" temperatures. Good insulation in the walls and attic is also important to keep excess solar heat from penetrating to the interior of your home. Also, keep in mind that light colored building materials reflect more sunlight and therefore don't absorb as much heat. So, light colored brick or siding will help keep your home more comfortable. Light colored roofing shingles or a highly reflective metal roof are also helpful. We painted our hardiboard siding a light cream color and, because the budget wouldn't stretch to metal roofing, chose the lighted roofing shingles we could find - Owens Corning Amber. You also want to provide a way to move excess heat OUT of the spaces where you actually live. In warm climates, high ceilings provide a place for excess warm air to go. And, if you build a two-story house, the downstairs rooms will stay much cooler during the day as the warm air rises to the upper rooms. So, if your daytime living areas are downstairs and your bedrooms are upstairs, you'll be in the coolest part of the house when it is warmest outside and in the warmer part of the house at night when it is cooler outside. This should help reduce the amount of heating and cooling you need to do year round Maximizing ventilation also helps to reduce your dependence on air conditioning. Operable windows on opposite walls allows for cross ventilation. This is especially good if you have windows that can be opened near the ceiling on the warm (south & west) sides of the house and opened near the floor on the cooler (north and east) sides of the house. Even on days when there is no breeze, rising warm air will escape from windows opened near the ceiling and will draw in cooler air on the other side of the house creating natural ventilation. Additionally, ceiling fans work wonders. They use very little energy but can easily make a room feel 5 degrees cooler. So, instead of needing to set the thermostat at 73 degrees, you can feel perfectly comfortable at 78 degrees. Just remember fans cool people, not rooms, so you should turn them off when you're not in the room. Finally, design your HVAC system so that the units and all ductwork is INSIDE the heated/cooled envelope of your house. Do not let your builder put ductwork and your HVAC units into your attic. Consider that most codes in Texas call for at least R-30 attic insulation (the equivalent of 9 inches of the pink stuff) but flexible ductwork has only about 1.25 to 2.5 inches of insulation around the central core that carries cooled air into your home. (R 4.2 to about R 6), Even when the duct work is brand new, isn't "leaking" or crimped or otherwise improperly installed, consider how much harder your HVAC unit has to work to cool your home when it must first push the cold air it generates thru 10 or 20 or 50 feet of ductwork that has only R4.2 worth of insulation between it and attic temperatures that may reach 150 degrees in the summer! And, flexible ductwork almost always starts leaking after a season or two which means everytime you do run your air conditioner, you're paying to dump cool air into the attic. Far better to run smaller ducts with less insulation through open web trusses within the heated/cooled envelope of your house. And, if the ductwork starts leaking, well, the cooled (or heated) air is going INTO your home where you want it instead of into the attic. Insist that your architect draw up the HVAC plan requiring the HVAC ductwork run inside the heated/cooled envelope of the house and incorporate that plan in your building contract. Otherwise your builder will probably insist that having the HVAC unit in the vented attic and having flexible ductwork running throughout the attic like a giant spiderweb is the "way we always do it" and therefore the only right way to do it. Do your reading and you'll learn that it is not the best alternative. Hope some of this is helpful...