greenhouse suck factor

I totally agree. and totally disagree-

I won't get into why i disagree, as i believe there are far too many people over intellectualizing the permaculture movement who ahve never farmed, and that they project their "ideal" notions of how the world should work from a place of privilege- not hunger.

Conversely in Latin America we are seeing an explosion of permaculture acceptance by the poor because it so easily resembles the milpa.

Bottomline- a greenhouse can make a poor family food sovereign in the cold north- and built and used properly it can be almost totally cogenerative.

In VT you can see "sunrooms" on the north sides of buildings for the view.

but growing greens without heat in a gh will be less carbon intensive than getting them from cali.



we are experimenting with earth bermed greenhouses but only in places where you get the minimum of 5-6 hours light at solstice- found and determined with solar arc finder.

VTers are having luck with aquaponics systmes and combining citrus and other trees in their greenhouses. The thermal mass of the plants themselvs actually balance temperatures as their root and soil mass hold heat.

Eliot Coleman has also figured out that low tunnels in greenhouses are more effective than heating greenhouses at all if you - have enough light. In fact light is more important than heat- his research has shown.

Unfortunately if we build exposed northern walls with a plastic r-value of 1 we will waste heat. so why build a greenhouse, when you can start plants inside a warm place under lights and impove into cold frame??

It really is nice though to have a greenhouse full of plants when it is -40 degrees out.

Ok it was just said that having a greenhouse isn't Permie..well the first book i ever read on permaculture..many years ago showed sketches and had info on building greenhouses..and was the first place i ever learned the idea of a chicken heated greenhouse..

The book was "Introduction to Permaculture" Bill Mollison..If you go to the Index you will find these references..Greenhouse as a cooling device page 82, as a shower area page 74, chicken heated page 153,essentials of 80 - 82,in cold climate 112 - 114,siting of 64,

pages 81,82 (window),107,113,116 (coldframe), show beautiful line drawings of use of greenhouse or other glass areas ...and this was one of the original permaculture teaching books.

so I don't understand the statment that greenhouses aren't Permie..that was one of the first impressions I got from reading the book and i had just purchased my greenhouse a few years prior so i was thrilled at more information on using it on my property.

Actually this book was my only information on permaculter for a long time..and i found it fascinating and very helpful even though it was not written for our climate i was able to adapt it to my climate by using the common sense information that was available in it to make a lovely property here around our home..it also encouraged me to glass in my front porch and to provide a shade porch on the rear of my house that we put in after the housefire..using the common sense beliefs and adapting to the climater here in Michigan

To what extent a greenhouse is "permie" or not depends on how much of its materials and/or heating method (if any) are recycled or produced on site as opposed to being purchased brand new or offsite.

In other words, a greenhouse made of cob produced on site and scrounged recycled windows is a lot more "permie" than one made of aluminum and polycarbonate purchased new from Home Depot.

Also, a greenhouse that is well integrated (makes good use of "waste" produced elsewhere, and itself produces only "waste" which can be used elsewhere) into a food-producing system is more "permie" than one that is not.

I don't think Mollison would look down his nose at those of us trying to acheive a permaculture lifestyle  in cool climates. The start of the thread was that greenhouses had a suck factor. In some cases they might be a useless expense or uneccessary. But a figure of 18% pulled out of the air is really not something that could be proved with any empirical data provided.
In my area I need a green house for many crops and have been successful in many of my efforts that do not require a greenhouse. But for tomatoes, peppers melons I need the protection of a greenhouse structure.
Hydroponics and aquaculture are venues that some purist (if there is such a thing as pure permaculture) might not approve of but I'm not takng them out of my efforts.
I'm trying to make my lifestyle as self sustaining as possible and will slowly work towards that goal.  In my cool climate it will be more difficult than other places I have lived, Wyoming and South Carolina, but it is a work in progress.
Will I ever acheive the ability to sever outside contact? Probably not, but I am enjoying the effort and am enjoying positive ideas and dialogue here. What works in some areas won't work for me and what works for me won't work in other areas.
Like any student I take and use what is valuable and viable for me and remember the rest even though I won't use it in my particular circumstance.
  Just because some one doesn't heed my advice on a subject (site of a greenhouse) doesn't mean that all greenhouses suck or that there are not some that are useful.

I ate some home grown tomatoes when i was in the country a few days ago and the difference between the taste of these tomatoes and bought ones was really big so i can understand Brenda Groth wanting her home grown ones.
    My grandmother had a green house full of tomatoes and  grapes, She was an efficient determined person, maybe you have to have your use of the green house clear to stop it getting turned into a junk room. Paul Wheaton says the temperatures in them are so up and down they aren't really good for seedlings I don't remember many seedlings in my grandmothers green house and she had a vegetable garden.

   It is the first time i have heard green houses questioned  it is interesting to think maybe they aren't so usefull for some things like that though they heat seed they subject them to such ups and downs that it is not really good for seedlings and then there is the question of how far north you are.

  Paul wheaton  mentions drums of water in green houses to conserve the heat in them and stop the temperatures plumeting at night. This is an idea the people who make pacific solar energy design houses talk of too look up "larry hartweg" in google and then tap on "zero energy design, abundant energy in harmony with nature" his house designs have a green house on the south side of the houses and use the hot air from it to heat the houses, if your are rich enough, with a swimming pool in it to hold the heat and to swim in, they are dreamy.

      There are, peoples green houses, made to provide them with house fruit and veggies better quality food or food which relieves them from food bills and whether they are used or not may depend on the time and efficiency of the owners, whether you are looking after small children or not, some moments in life aren't good ones for extra jobs you might find you use it later in your life.  There are also industrial green houses and i don't know how to evaluate their value.
     I have just been looking at Bill Mollison youtube videos and he has a follower with a green house that he says gives valuable heat in such a cold part of America as the one this man lives in, "temperate permacullture structures part 1", so green houses are kosher permaculture, though they may not be Fukuoka as he insists on keeping things simple and not giving ourselves work. It is very kind of him to want to keep things simple and get us working less so that is a good reason to really inspect all the things we use to see if they really help us. Also it is not part of what mnature provides for whichever place the green houes is in maybe you get more plagues in them.
 Here in Spain there are whole big areas of green houses in the south that produce winter, summer vegetables for the whole of Europe. I suppose they are not the only one producing these. The Moroccans immigrants work in them and my heart bleeds for them, i imagine that the herbicides and pesticides in a enclosed and hot space and i think it must be a canceriginouse job. I have not researched this, i just imagine it to be so. Is it moral to create nasty jobs for people? I suppose permiculture should be greening Morocco instead of us giving Moroccans poisonous jobs. We should be able to get by on cabbages and leaks, maybe, winter vegetables, it really makes life more exciting when you can't always have everything at everytime of year.
  In the last month or so under the influence of this blog i have looked up permaculture videos in youtube and found a video of Geoff lawton, "greening the desert", it is the first video in the ones that appear if you tap in "permaculture" and press search, at least it is for me. He makes a disapproving mention of the green houses they use by the dead sea were he was greening the desert his greening the desert  was really interesting but he does not go into whats wrong with green houses. agri rose macaskie.  

Rose,
I absolutely agree that there can be wide temperature shifts within a greenhouse if not monitored and mitigated. My first year as I have mentioned was a dismal failure other than the hydroponic greens later in the season. But the addition of the large volume of water that was used to pump through my hydro system did temper the fluctuation dramatically. The addition of sunshade the next year, a more elaborate but scavenged photovoltaic fan system again added a more successful season. I have a greenhouse attached to the house as well and all my seedlings are started there. The greenhouse is just a tool and you get more proficient the more you use any tool. As with any tool you sometimes have to sharpen it or adjust it to get it to work right.

as you mentioned grapes growing in a greenhouse..i have thought of adding a couple of grapevines to the north end of my greenhouse..but have not come to the place of doing it yet..but it is constantly in my planning for the future..we have lots of grapes on our property..but our northern exposure does make grape growing more difficult than more southern areas..i do have grapes on my vines right now..but many of the locals have lost their grape crops this year to molds and mildews and rot from the cold summer..i have been fortunate..but if i had them in the greenhouse i'm not sure how they would fare..might try this next year.

sometimes when i read things like the book on eating within 100 miles..etc..i realize that maybe i shouldn't even be allowed to eat tomato and pepper products as they are tropicals and i don't live in a tropical place..but we like them a lot and they are very healthy products for us to eat..so i grow them in my greenhouse..and am glad that i do.

i get more than enough for fresh, canning and freezing..and probably could dry some but haven't.

i likely will continue to grow tomato and pepper plants in my greenhyouse until i die..i have rosemary in there this year for the first time and i'm going to see if it will survive ethe witner unheated int the greenhouse..hoepefully it will..i do have a list of plants i would like to try growing inthe greenhyouse..however..it is very small and i'm not interested in getting a larger one.

i do have the wood boiler buildling that last year maintained about 50 degrees all winter inside..and i'm thinking of possibly putting a small glassed in area off of the SE corner of this building some time..i won't get to it this year..and if i do..it might be a place that would be more useful for experimenting with year around crops..then i wouldn't have to actually heat the greenhouse..per se..next year i'll keep my eye out for some salvaged glass to consider glassing in a corner of that building..or putting a small glassed in extension on it..close to the boiler..and then possibly that will be a way to expand my greenhouseY type of forays..myh front glassed in porch getsw way too hot and way too cold to grow things there..but it does helpt o heat the house in the winter..which was it's purpose..and the cats love it....but to heat it at night would be a waste of heat....at least for now..this has been an interesting thread..but honestly..i think hard and fast rules are just a foolish thing when it comes to life..as there are so many differentials in climate and people..

our climate demands that we protect our plants if we want them to produce..we had less than 90 days between frosts here this year..and the coldest summer and the coldests winter on record for this past year..so i know how difficult it is for pepole from warmer climates to even understand that..in Michigan, wind breaks and shade are both needed..to warm and to cool your home..and greenhouses and hot caps and cold frames are a must if you want to grow tenders..

we have friends that have a market garden near Lake Huron..and they have a couple of hoop houses..they grow their tenders inside of those until it is safe to set them out..if they didn't..they wouldn't have any to offer to the area at farmers markets..that would be a shame..as they are the only farmers markets growers here to offer hot pepeprs ..it might not matter to those living where they can pick a pepper intheir garden..but here..that is just not possible

  Hard and fast rules are often stupid but talking about all the for and against is reall usefull it turns up lots of ideas clears out some stupid practices maybe. agri rose macaskie.
 

I'm in zone 8b/9a, northern Florida.  I have a greenhouse.

My greenhouse rule: I will do with it as I please and leave you to do with yours as you please.

At this time the old one is coming down, a new one is going up.  The old one I put together with scrap lumber I had lying around. 4 2x10s standing on edge made the square base, 4 2x6s upright at the corners, 4 2x4s made a square roof frame.  A little more lumber and a door, the thing was done-a 8x8x8 cube.  I first covered the whole thing with 6 mil visqueen, stapled in place on a 60 degree Thanksgiving morning, 3 hours later, it was 110' inside.  For the next 5 years it was a process of accumulation and redneck engineering.  Lighting was added with an extension cord, some spare wire, a couple of $3 jar lights from the hardware store.  The roof was held up with 3 sections of PVC pipe after the rain turned it into a bowl hanging down a couple feet.  A diagonal brace was added.  The north wall was covered with scrap plywood.  Shelves were added as I came across suitable lumber.  Water was a garden hose shove under the frame.   I did some work installing doors and windows for Lowe's, picked up enough sliding glass doors to cover 3 sides. 

I did spend money on heating in the winter.  I got a 55 gallon plastric drum from a guy for 10 buck.  This was filled with water and an 8 watt fountain pump added.  The pump moved the water through 500 feet of black PEP hose, irrigation hose, which was coiled in the driveway.  Pump ran off a timer so that when the sun hit the hose, the pump would start then stop when the sun went behind the palm trees.  I'd get the tank up to 100-120 most of the time.  Come morning it would have cooled to 40-50, but kept the space warm enough.  Never lost a single thing to frost.  The power to run the pump cost about 12 cents per month. 

I use the greenhouse for seed and transplant propagation.  Being a 1/4 acre property, there is only so much space for a garden.  By reducing the time the plants spend in the beds, I greatly expand production.  Plants go in with a deep root system so they can withstand dry conditions, thick stems so they can take a hit from cutworms, and are spaced for optimum production.  A plant comes out of the beds, I've got another one ready to go in.  I have only 750 sqft of beds, but I get all the produce I need for me and my neighbor. 

Cooling was never a problem.  With the visqueen cover, it never held up for long with the Florida sun.  I cover the thing in November, by April it was worn out.  No roof sucked when it rained so I eventually covered it with corrugated polycarbonate sheets.

The new greenhouse is being built in the driveway.  At 9x12 it will offer plenty of room to move around.  I'll even have space to keep warm weather plants.  Nothing wrong with tomatoes in January.  I'll try to get some pictures up.  Should be done in another couple of weeks.


edited for spelling

paul i agree fully with you on the first part in your first post, about there being a small percentage of greenhouses built, that actually server the purpose they were built for. i live with a family that has one of those "uh oh" greenhouses. when it was time to build this greenhouse i said you need to think of things like sun exposure, shade, wind, etc....basically i said you need to build a solar greenhouse and build it like this......well, i was also labeled a negative nelly so to speak. long story short the greenhouse was built with looks in mind, over function. and the greenhouse can not handle what winter can throw at her, it does well into the high 20's but once it got to 20 or below our 15ft tomatoes were toast.

that being said i dont think greenhouses are a waste, or even a separation from nature. the greenhouse here even though not perfect. THRIVES with life. we have so much natural pest control in there its not even funny. i have seen 3 species of frogs, 2 lizard species, countless predatory insects. all in a 12x20 greenhouse. no problems with pests.

Greenhouse..........  Well I call what I have more of a cold frame.

I am in the south.  A sealed up greenhouse is more like a steam cooker for plants in the summer and even on a hot winter day.

I now only seal up my "greenhouse" on freeze/frost warning nights.  Otherwise it is pretty open on the ends during winter here.  In the summer, it is only a roof as I remove the sides completely and there is shade cloth over the top.  This allows me to keep the tomatoes and peppers growing as perennials. 

This cold frame is over the aquaponics system and last year I tried to grow tilapia year round but have since decided that they are too close to being tropical and we like the catfish better.  See to keep the water warm enough to make the tilapia happy, I was having to keep the greenhouse sealed up too much to try and regain heat, result was the water wasn't much warmer but most of the plants suffered from too hot/humid during the day and still too cold and wet at night.

So, Things seem to be growing better this year already with my change in management.  Tomatoes and peppers are still happy by keeping them from freezing but I'm still managing to grow cool weather crops as well.  We have harvested most of the tilapia and I will not stress over keeping the water too warm so this won't cost extra this year.

As to the suck factors.  If you don't plan properly, a greenhouse can become worse than useless.  The humidity in a greenhouse can easily cause huge fungus and mold problems if you don't control it.  They can easily get way too hot in summer and still be too cold in winter.  Lots of research should be done before investing in such a thing.  Winter sun is important and summer shade can be too.  Or simply opening up the sides or having roll up sides can completely change the usefulness of a "greenhouse."

I guess they should be treated like every other item in a permaculture design.  With all aspects of them being carefully thought out as to usefulness and functions they can fulfill in relation to resources they will use (space/energy/maint/etc.)  What is appropriate for a greenhouse in one location is pure folly in another.  My greenhouse was pretty inexpensive to build, some posts, some boards, some cattle panels and some plastic.  Would not be a good idea for anywhere with regular snow, tornadoes, or hail.  All I need do to make it hurricane safe is knife the plastic on the roof since the sides are removed already in summer.

My new "outdoor kitchen" is also a bit of a cold frame.  It has white tarps for the top and sides and for freeze warning nights I can put plastic up on the ends as well and I can keep tropicals from freezing back that way.  Will see if I get more bananas and papayas this way or not, the white tarp might block too much light, we will see.

Ground breaking news here folks!I know it seems hard to believe,but people have been living without greenhouses,running water,and rototillers for a long time.Some of themeven in areas where many of you claim to `need` a greenhouse.I have personally worked with almost 1k species of plants that provide needs and dont require a greenhouse.hmmm

26 degrees below zero in our area the last week. Double coverage in greenhouse without external heat input. Cabbage, leeks, carrots, claytonia and spinach still green and alive. I love my greenhouse.

Mt Goat, if you don't want or need a greenhouse, that's just fine with me.  Your convictions fit in with my greenhouse rule: I will do with it as I please and leave you to do with yours as you please.

I agree.And if people are not using industrial products and supporting the destruction of the planet that I need to survive on then they are leaving me alone but unfortunatly the oil,coal/elec used to manufacture a greenhouse has real world costs that just happen to effect me.Just like the lowering of ground water by people using irrigation effects me.If people keep the ecological costs of their endevours in their space,then yes,we dont have a problem.Im assuming those with purchased green houses will jump at the opportunity to have a LOCAL greenhouse manufacturing facility within breathing distance and are advocates of oil pecurement for plastic or coal mining for glass.If not?Perhaps Im mistaken but I thought this thread was for ranting on greenhouses which,due to my interest in sustainability,have 10+yrs of experience in.

By not using a greenhouse,Ive had to utilize some of the other INFINATE options to meeting my needs and low and behold,ten years later,Ive developed a lifestyle not dependent on a greenhouse.Now Im not gonna fault someone for using what choices they can see to survive within the existing social structure.But if you need a greenhouse to do that .then getting one just treats the symptom and a closer look at the root cause of needing such a techological crutch might be in order.

At some point the purchase of a tool or greenhouse that can not be produced locally yet extends or improves the harvest/productivity would be a positive.
If by using a greenhouse I reduce the use of fuel to transport products into my location that would be a positive.
If a greenhouse is made of salvaged materials that would be a positive.
Initial cost and impact spread out over the life of a tool or greenhouse has to be considered. Just because it came from outside the local area does not make it bad if it's purchase and use are effective in reducing impact from other sources.
Deliberative thought has to go into purchases and in my area a greenhouse is essential to extend what is a short growing season.
A shovel, rake, hoe are not locally produced in my area yet are tools that I need to produce. A prudent and intelligent choice since to create a facility to produce them would be a foolish waste of resources.
In some cases a greenhouse might not be a wise choice depending on materials used for its construction, orientation of the structure  and what one might get from its productive capabilities. In my case and I'm sure many others a greenhouse is a structure that makes sense.
When I lived on the west side of the cascades I didn't need a greenhouse. In South Carolina I didn't need a greenhouse.
  A tree that bends with the wind does not break, you have to adjust to your locale.

I believe that improving the harvest using a greenhouse is a `positive`for YOU.Probably not to positive for those things on the production end of it though.One of the best ways to rationalize the present as `progressive`is to compare it to something worse.So yea,their are worse things out there than a greenhouse.By having/using a greenhouse,you are a de-facto improvement.But why stop there?compared to whats possible sustainability wise.Greenhouses `make sense`until your knee deep in the middle east.Cant agree that greenhouse dependence is `adjusting to your locale`or being flexable.Just the opposite actually.How about `adjusting your loacale`.I do consider them `adjusting to the social strucure`as living like a native is pretty much illegal and your pretty much trapped on your property so you kinda gotta have to `adjust your locale`just to survive.

RawVim wrote:
Greenhouses are in the south for the same reasons as there are greenhouses anywhere else.

Jim

Depends on how south you are. For example, in Costa Rica, we have greenhouses, no heating, obviously, but they have shade clothe and plastic. Shade so that you cut down on the sun, and plastic to try to keep the soil reasonably dry.

You almost can't grow tomatoes without this.

To point a finger at everyone who might own a greenhouse and say they are knee deep in the middle east oil is so easy.  To divorce anyone in the United States and say that they have not or are not benefitting from oil at some point I think is difficult. Right or wrong.
Have we or do we use an asphalt road?
Have any furniture that has foam rubber?
Ever owned or driven a car?
Recieved goods transported from another area by any internal combustion machines?
Live in a modern house.
Have nothing that is made from plastic.
Use electricity?
Hot water?
Lumber?
Woven cloth.
Sewer infrastucture?
Water infrastructure?
Well drilled by a machine?
Use any modern tools?
Paper?
Read a book, newspaper?
Telephone?
Parafin wax?
Ever eaten anything produced and packaged by some one else?
Benefitted by an emergency response vehicle.
Ever been treated by modern medicine.
Gone to school?
Clothes manufactured of cotton?
Clothes manufactured of man made materials?
Clothes made of hemp and processed by machines?
Unless we live in some kind of macrame impervious bubble and have never set foot on a sidewalk we have benefitted from oil. It's a cross we all have to carry. Now how to mitigate what we have done, and acknowledge responsibility.
So essentially depending on where one lives and how old they are they might have a bigger oil footprint than I have. But if you live in North America you have one like it or not.
Hard for me to make a leap from social structure to a greenhouse structure.
Learn, adapt, overcome a greenhouse used properly lessens my impact.
Count the things that we touch tomorow without the scent of oil or coal on them.
 
 

I use some of that stuff.Civilization controls just about everything although when I read your list,I laughed cause I actually use very little on it.Gone to school=forced to school.Set foot on a sidewalk?unfortunatly.Sewer infrastructure?haha-havnt used a toilet in 10yrs. But yea,I`m forced to participate in history like the rest of us.That doesnt mean I have to like it and I certainly aint gonna spend my time promoting it but if someone is promoting it,Im gonna speak out against it.I believe its the right thing to do!Someone might get on this site and say"hey,hes got a point!""why dont we NOT get a greenhouse and instead spend our limited time and money on some of the unlimited other options toward food security"Those people will be creating the permanent cultures of the future.Not perpetuating this clunky inefficient evolutionary dead end known as civilization!

where i am shade houses are required, so i planted a tree that will have a canopy spread of around 100ft, until it grows its use the shade already there shade house may come one day buts its not high on the list,

I've looked at a few greenhouses.  Some used for residential use, some on farms, several commercial growers, and 1 monster that was just used to grow hydroponic tomatoes.  I've built 3 for myself, 2 for other people.  I've seen productive uses and I've seen a few that are little more than covered storage.

Commercial greenhouses are the big ones.  A hundred feet long, hundreds and thousands of plants, all the buzzers and whistles.  Often, the efficiency of scale makes these cost effective and highly productive.  They were planned right, built well and serve the needs of the industry or enterprise that operates it. 

Residential greenhouses are another matter.  Many are purchased and erected on a whim.  Someone with more money than sense.  Maybe they saw one on TV and thought it was cool.  Maybe they know someone who has one and are just keeping up with the Jones's.  For whatever reason, There are lots of greenhouses where the owner had good intentions and lots of excitement but little knowledge or need, the excitement waned, and other distractions left the thing sitting in the corner of the yard unused.  These are the fad greenhouses.  They seemed like a good idea at the time, but in the end proved to be a means of separating a fool from money.  Lots of people buy things they never use, greenhouses are no exception.  Rather than rail against greenhouses as being wasteful, it might be a better cause to rail against stupidity.  Greenhouses are limited, stupidity has no bounds.

I've seen greenhouses that are busy, active, and full of life, kept up by an attentive owner who is highly motivated and involved with it.  Roses and orchids, cacti, lilies, amarylises, flowers and ornamental plants, every color of the rainbow and for every season of the year.  They use all the fertilizers and herbicides and pesticides, root hormones and water conditioners.  The end product is certainly pretty, but for the resources consumed, I would prefer a product with a more practical function.  I've seen greenhouses with aluminum frames, rubber gasketed double walled glass, stonework stemwalls, marble sills, and better climate control than I have in my house.  It would be the pinnacle of rudeness for me to insist they should be growing vegetables to eat instead of flowers to look at.  Its their BBQ and it tastes good to them. 

We are all connected and the herbicides and fertilizers they use end up in someones drinking water.My sister bought a house near a small greenhouse operation and the nitrates in their well water are rising.Is that not the pinnacle of rudeness.Why blame the victems for complaining?.The reality here is that greenhouses have ecological costs and that those effect real people in real ways.To just discount that imo is the pinnacle of rudeness.I dont believe humans are stupid other than weve created such a confusing ,tangled mess that we are no longer capable of understanding the ramifications of our actions.
You will note that this particular thread is explicitly about the downsides of greenhouse and while I relise that some are on this forum to strickly pat themselves on the back for saving the planet(with their greenhouse),I feel it is of upmost importance to point out the downsides that I know about.

I use no chemicals or processed inputs in my greenhouse or garden.  Each plant I grow and consume is one less plant that needs to be produced in a manner that poisons your sister.  My neighbor gets stuff from my garden, which was started in my greenhouse, that further mitigates poisoning your sister.  Since the food grown in my yard does not need to be shipped thousands of miles by diesel trucks, the air your sister breathes is cleaner than it would have been otherwise.  My greenhouse is built with salvaged and scrap materials that otherwise would have ended up in landfills causing more pollutants in the groundwater.  The plants are grown in plastic cups I dug out of my brothers garbage can at great personal risk and are reused repeatedly.  The water used comes off my roof.  It is untreated and took no petroleum fuel to pump, hence no added air pollution or waste heat to contribute to the destruction of your sister's environment.

I'm doing what I can for you over here.

Ah,thanx for trying.All we really can do is the best we can with what we know where we are at and it sounds like your efforts are a big improvement over what your other options appear to be.Clearly,there are many variables in analysing greenhouse pros and cons.Reusing stuff can be a great solution in the near term and its pretty hard to critique reused materials from any angle.

This is a very interesting thread, I will continue to watch this over time. I just wanted to tell the group that I have been watching the dumpster at one of our local window replacement shops.  They have a gondola out back that gets hauled away every two weeks, I spoke with the owner about taking something out for my own use.  He stated that he pays by weight and size, so taking a few things out actually saves him a few pennies and it helps me.  The last dumpster run provided me with five wood framed patio door insulated glass units, with clear tempered glass in them.  I had to pull a few staples out of the edges but that way it.  A few more units and I will have enough glass, but there is much more planning to do before anything gets built as a structure.  Possibly this will help others obtain materials cheaply.

I work for a glass company, but I cannot order the glass this cheaply. 

Mt.goat wrote:
We are all connected and the herbicides and fertilizers they use end up in someones drinking water.My sister bought a house near a small greenhouse operation and the nitrates in their well water are rising.Is that not the pinnacle of rudeness.Why blame the victems for complaining?.

But is it the greenhouse it's self making the choice to use herbicides and fertilizers to the point of getting into the ground water?  No, it's the people running the commercial operation.  Even if they were growing without the greenhouse a big nursery operation or whatever they are running could cause those same drinking water issues and actually probably even worse as it is harder to control the amount of water used in such an operation when under an open sky.  It is often about attention and labor at that point.  Too costly to have employees hand check and water the stock so they run the automatic watering systems as a matter of course if it's needed or not.  The greenhouse isn't changing that.  Actually a greenhouse just keeps it contained a little better since sprayed products used in the greenhouse are less likely to drift directly over to your sister's house, she may be getting protected a little by it.

All I'm really saying here is that the greenhouse is a tool not the person or business deciding to use the bad chemicals.

The point of this thread I thought was to highlight the down sides of greenhouses so that people thinking about using them will think carefully and not build a useless wasteful greenhouse.  When used appropriately a greenhouse is no more wasteful then the house you live in since the functions it fills outweighs the resources it consumes.  For those that are going to build a greenhouse that gets full summer sun and complete winter shade, well they would have been better off building a shed.  Or like the guy asking me which lettuce variety to grow hydroponically in his desert greenhouse in a hot climate with no meas of cooling the greenhouse.  "I'm thinking dude who wrote your business plan and let you do such a thing?"  He didn't understand that lettuce doesn't like 120 degree F heat but had invested huge in a greenhouse to run a business growing lettuce in a middle eastern desert.  Sigh.

So it is probably not necessary to vilify the people here who actually use their greenhouses to grow their own food likely with minimal chemical herbicides, pesticides, and fertilizers to pollute your water.
Claiming that all greenhouses are evil because some commercial business near your sisters house is polluting the ground water is like claiming that all farming and gardening are killing the planet because big ag uses chemicals and depletes it's soil.  Not everyone has the choice to find the perfect location to buy land (and still make enough money to pay the taxes) where they can support their family, so they do the best they can where they are at.

One can't overlook what current society has allowed us to accomplish, whether we want to admit it or not for instance Mt Goat your 15 acre infant orchard is a result of the current societies governement and oil dependent infrastructure. For one to say I refuse to use that infrastructure now doesn't negate the fact that no matter how much one wants to divorce themselves from it they a part of it. Should that infrastructure crash at some point their hard work might be for naught. Security of our current society is the result of  that infrastructure however fragile that security is.
Am I happy with current government and our dependence on finite resources, no. I want better.
If we live here we are an integral piece of the current model though we want to be disconnected.
What would be a a greenhouse that had less impact than what you opposed?
For example near here is a fellow that has a greenhouse that he has constructed of straw bales and reclaimed windows and sliding glass doors. Localy produced wheat straw. salvaged glazing. is that 1% better on your scale? 10%.
As far as nitrate contamination of well water there are really is some pertinent data that has to be identified before you can effectively say that nitrates are coming from a commercial entity and not some other non-point source.
Level depth of oxic and sub-oxic water, depth of well and signature of the nitrates identified in the well water. If she is on a well, I assume that the area is not served by sewer? It could easily be from some other source than a greenhouse, though it could very well be the source.   A neighbors leaking septic waste. Farm silage. Even buried vegatation can cause an elevated nitrate signature.

Yes,A greenhouse is a tool and it can take a lot of pollution to create one.That pollution might be spread into the enviroment we all share where it might not be quantifyable anymore but would,non the less,be there for us to breath ect..so pestecides aside,just the construction of a new greenhouse in itself affects people and planet in a negative way and may therefore,constitite a downside.While a purchased greenhouse may pay for itself economically,the amount of resourses and pollution required to manufacture and deliver it make it hard for me to believe that a person would ever get a caloric return on that investment(regardless of how well it was used).I have made effort to keep my critique largly on purchased greenhouses here.My main point is that nobody NEEDs a greenhouse and there are alot of other activities that are more ecologically responsible and have a higher caloric return.We can use our limited oil(and I DD)to set ourselves up for not needing oil or we can develop dependence on industrial products by choosing to integrate a greenhouse into our homestead/lifestyle/culture.

Would you agree a greenhouse produced from locally salvaged material reduces impact to some degree compared to a newly purchased greenhouse?
Does salvage or reuse add or detract from your balance sheet of impact?
I guess I can see a debit impact of a particular manufacture of a product but if it is reused after it's projected life span does it then begin to pay back?

If the only way we can justify a greenhouse is by comparing it to worse options,then we have a problem.While most of you seem uncomfortable with my critique(a little close to home?),I will continue to speak out against what I believe to be a monumental waste of energy and resources-greenhouses.I will also work tirelessly toward providing examples of more ecologically alighned activities that have higher caloric return ratios.Those who purchase a greenhouse should take responsibility for the ecological costs.Those who salvaged a greenhouse have still made themselves culturally dependent on the oil/surpluss but avoid the `karma`of directly supporting the oil companies.I will reiterate here-IMO-1.purchased greenhouse-least efficient/worst.2.salvaged greenhouse-better.3.changing culture so greenhouse not neede-most efficient/best

I enjoy the dialogue  but this is something we will not agree on.
Even though some are semi divorced from society do you have any karmic responsibility for the time you have been in the current society and benefitted from its dependence on oil?
When does ones payback begin and how does one measure it.
Though the romantic notion of going back to a native society is appealing to me, I've seen third world poverty and subsitence life without protective societal norms and hope to create or be a part of  creating a better forward looking system that for my area includes greenhouses.
Any comparison has perfect and less than perfect points.
Does the fact that we have an impact and a connection with the support of oil dependency hit close to home for any of us? It should, until we all agree that we are part of the problem we will move forward slowly, perhaps too slowly.

I have never denied my use of oil to get where I am,but I will deny my dependence on it for food production.I am,unfortunatly,karmicaly tied by fate to its use but that doesnt mean I have to support it.I dont count many of the benefits of oil listed earlier as benefits.I`m not going to thank civilization for solving problems it creates to begin with like"now that the sustainable culture that developed over thousands of years here has been destroyed,civilization gave me a plastic greenhouse to survive.yay!" There is unlimited potential beyond the 3rd world vs civilization dicotomy!I understand and relate to your fears about security in an uncertain future,however,I believe that putting your faith in civilization/system/progress ect...is acually the sourse of those fears and that true peace can only be attained through a close and trusting relationship with the earth.A permanent culture is more secure than dependence on technological crutches.

Civilization claims to satisfy our need for security by selling us the image of security in the form of products.That these products dont actually satisfy is all the better for buisness.First they destroyed the sustainable examples that did exist(indigenous land use),then they profit off our insecurity by selling us things like greenhouses?!?I`m not going to thank them for attempting to exploit my fears.I`m actually annoyed and am going to run their little game(civilization)right into the ground!

Mt Goat
Religion, government, tribes, could all be saddled with the same description of providing security through prayer or numbers or promise of protection. If you distill its purpose governments are formed to protect the people. And whether you or I agree on its efficacy to date we have chosen to live under this governments protection and misuse of resources. There are no fences to keep either one of us from leaving. Trust me on this though, Somalia should not be on either one of our lists if we choose to go someplace else.
You have worked under the umbrella of protection and current societies misuse of finite resources to achieve what others in third world countries have not been able to or have access to. Now, once you have acheived some type of imagined security through your vision of sustainablity you sit on high and point at others and condemn their vision or pursuit. I think you are wrong and you think I am.
Our anthropologic ideas differ in that many tribes were opportunistic in their harvesting techniques. East coast estuaries for example were inhabited until oyster beds were depleted and easier pickings were farther down the beach. Perfect when there was no one else down the beach. Conflict for hunting grounds were a fact of their existence.
I'm not fearful of the future but want to change it to a better vision than what I see as coming to fruition with the current mindset.
Changing civilizations idea of what is right is a better use of my time than running it into the ground.
I get the picture you don't like greenhouses. I do.

Its true that I have a close relationship with the earth and trust its ability to provide for me so I feel empowered to diss the system.Its also true that having that relationship is discouraged in this culture and it is only through my position of relative wealth and privilage that I have had the time to re-discover that relationship.That relationship has been and should be a birthright and not elusive.My privilage has given me the time to set up the forest(at great caloric expence)for future production.The only reason it takes so much work is because no managment activities have taken place for over 100yrs.Had I been born into a sustainable culture,there would be no break in managment and thus less work.That the system sets up hurdles to sustainability should be a critique of the system.That I was able to overcome those imposed hurtles should not be used as proof of the systems success.Yea,I`m not really into the whole oil/coal/greenhouse thing.Reality is what you can get away with so have at it all you greenhouse lovers!

Greenhouses are like any other gardening tool.  Designed properly, they can greatly improve the productivity of your garden.  Designed poorly, they can be a great waste of effort and resources.  Here, I use what might be considered either a small greenhouse or a large cold frame that I assemble over my beds to keep them in production all winter long in a zone 7a climate where they would otherwise be shut down for 3-4 months except as a storage site for root crops.  By keeping the garden beds productive, I can extend the growing season for summer crops, keep the cool season crops growing well all through the winter and reduce the need to can or freeze as much produce as I would otherwise need to do. 

Currently many plastics are oil dependent but there are plastics being made of plants. Perhaps if the greenhouse glazing was made from a product not dependent on oil that would lessen your opposition. Maybe that will be an option in the future.
There are many permaculture practices that do not require gizmos but a massaging of the immediate local environment. Berms, swales or a raised bed are not any technological miracle.
There is no argument that  we have to reduce resource waste. What I have an issue with is to say that permaculture is an idea that requires a tremendous input.
Just look at the posts for synonyms for permaculture many have different ideas of just what it entails.
When I think of permaculture it is "permanent agriculture" and had never given it the broad vision of permanent "culture". If we add that idea of some type of governance/survival that a "culture" requires, it becomes a much larger vision.
Once people create an environment that I believe is possible on small parcels of land that offers sustainability I can see a switch from my permanent agriculture vision then encompassing an idea of permanent culture.
Small steps to start with, a big chess game with strategies is the way to play.
My wife carpools, there is an expenditure of resources to get the four people to work. The expenditure reduced by 75% is an intelligent reduction in resource use and spendable income for those that she pools with.
  If by using a greenhouse I reduce the need for external input from transporting food, shopping for food, storing food elsewhere, I see that it is an acceptable resource expenditure. If the greenhouse does not or is not used intelligently than I see it as a waste of resources back to Paul's original premise that some greenhouses "SUCK".
I like where I live, I have lived in areas that are more garden friendly. A properly maintained and utilized greenhouse doesn't have to be a resource liability.

If everyone carpooled its not going to change the fact that most jobs in civilization are pointless.I highly recomend the Derrick Jensen book As the World Burns-50 simple things you can do to stay in denial.Its a great critique of incramental change within a dysfunctional system. I think its fair to place the ecological cost of the 82% of the greenhouses used inefficiently on the concept of "greenhouses" itself.A famous agriculture writer talks about this.People saying "farmers just need to do this or that""those farmers need to wise up!".Its pretty easy to shift the burden of 82% useless greenhouses on"those stupid people"Is it fair to blame the people for being uneducated or stupid when the sytem is overwhelming them with information,choices,and demands?.Are advanced monkeys even capable of using industrial technology for `good`?If the production of said technology is `bad`?If its not working now,should we carry on based on this ever elusive`potential options`in an unkown future?How much of the present earth should we sacrifice for this future?.