I wanted to reach out to you about a really exciting, important project I have been working on. I love all of your guys work on this platform to restore ecosystems and water, and so I wanted to share this with you all because I think it's something you may be interested in. Ten years ago, it was just a dream of mine to build ponds and help regenerate landscapes as my profession, and I have made that happen...but there's only so much a single work crew can do.
My dream for the next few years is to start an online learning and training platform that can teach thousands of professionals how to restore water to landscapes, and help their communities put water restoration into practice.
This platform, I believe, has a ton of potential to decentralize water restoration, but we are still in the beginning building stages, so please give us any feedback about what you might want in a platform like this.
Please visit our Water Stories Website to see more details and sign up for the newsletter there for updates when we have them.
We are going to be launching a Q&A with myself soon, so if you sign up for the newsletter you will get updates about that too.
I have been blessed with incredible mentors throughout my life, leading me to experience firsthand the magic that happens when humans partner with nature. A world more beautiful than we can even imagine is possible. Yet, if you tune into the news today you are left with snapshots of a world in despair. You see the many environmental and humanitarian catastrophes and conflicts around the world, but what a lot of people don't see is that these are a result of our relationship with water. The severe anthropogenic disturbance of the earth’s hydrological cycle is leading to increasingly extreme climate, and cycles of flood, drought, and fire. However, the ability to rebalance the water cycle and mitigate extreme climate is at our fingertips, but we all need to look first to nature for answers to find the true solutions.
How do we distill this understanding down to the most essential parts, so that it can be easily communicated to others? That was my goal when I set out to do this TEDx talk.
If you are distraught about the state of the world today and looking for tangible actions you can take, this talk is intended for you. If you want to help restore global water cycles and create a world of abundance and health, please share this video as widely as you can. Humans need to know what is possible to move into action. Building awareness about the immense possibilities and potential is the first step.
Casey Pfeifer wrote:Loved the video Zach, thank you for posting Cassie!
I'm curious, would you happen to know what the yardage limit for an earthworks project is for it to not need a permit up where this project was installed?
Yardage limits vary greatly depending on location and regulations, California, for example, is 500 cubic yards. I feel so very sorry for the people of California, they live in a truly dire situation with dysfunctional and idiotic representation. The watershed degradation there is on par with Syria, yet the regulations are so extensive they actually prohibit restoration or regeneration. For a project we are currently working on in California the permitting for the water body will likely cost more than building the water body itself. This kind of stupidity, in a region where this work is so desperately necessary, I cannot understand.
what--if any--sort of permits were required to make the pond? Just south of the boarder where I live, we have LOTS of regulations, and I worry that if I made a pond, it would be classified as a wetlands, and would then be protected by our wetland laws and require a wetland buffer zone. Do you know if there a way to make a pond without it becoming a protected wetlands? While I have nothing against protected wetlands, 1/3rd of my property is already protected wetlands, and I'd like to use what I have remaining.
We currently have a small stream fed pond on our property that was dug by the previous owner. He dumped concrete and put a plastic liner in there (which has, of course, degraded), and the pond almost entirely dried up two summers ago. Are there ways people can optimize their current water features to help them retain more water?
To your question Nicole in this case it is a dugout fed by rainwater so no permitting was required. BC has some very strong right to farm legislature that really protects the farmer cultivating their land. I think this is important legislature to be passed everywhere, people have to be able to work with their water and their land to start making an impact.
The US is rivaled only by the EU with regards to litigation and legal/permitting turmoil, it's certainly never easy. In the US the important pieces are where is the water coming from and what is the volume of earth being moved or water being retained. If you stay under their limits there is still a good bit you can do. Often times you just need a geo-technical engineer to sign off on the dam construction when the dam is over a certain size (a very logical thing). But there are other places where people don't own their own water and so run into troubles impounding it in a water retention feature.
There are LOTS of problems with our current wetland legislature, namely that it doesn't allow for regeneration, enhancement, or expansion. Yes as you are describing can happen, but if it is a permitted (or doesn't require a permit) water body that is man made you have a strong case. That's unfortunately how our legal system works, nothing is ever as cut and dry as it seems.
There are also laws that require homeowners to remedy resource concerns for themselves of their neighbors when a problem is recognized. In your case you have very good cause to come in and rix everything, in your case possibly rebuilding the pond as an earthen feature. These are the only types of water bodies that really aid in watershed restoration and climate balance.
Chris, yes this is exactly what beavers do. But we killed off all of the beavers and drained the wetland for arable land for agriculture. That's why it is urgently necessary for humans in modern times to act as the beavers did, re-hydrating land and acting as keystone species for the regeneration of the earth's organs.
I like the beaver habitat in the boreal north idea, that could really have some merit!
Sounds like a great time! I'll be driving cross country between projects in the east and ones in the west, sometime mid to late June. If the dates coincide I will certainly be stopping in to enjoy in the festivities!
Not sure if you found someone to help you implement Holzer's approach at your place or if you've gone in a different direction but it's looking like I will be coming to New Zealand and NSW Australia for two different projects this December/January. I would be happy to add your project to the trip if you are still interested as I will already be in the region. If you're still interested send me a contact form or email through my website:
Well this question kind of opens up a can of worms, but long story short the organizers we were working with at that time had their own agenda and Sepp was never on board with offering certification for merely 30 days of workshops and one successful project, even though it was presented to us otherwise.
Currently I am the only person Sepp has personally certified (he said because I am so talented, his words not mine). There was the year long training program at the Krameterhof that Sepp used to run, that is now continued by his son Josef, but that is a different experience, more like a PDC - attend, do the basic work, and receive a certificate.
This I can say, I graduated summa cum laude with a degree in ecology, but earning certification from Sepp was at least an order of magnitude more difficult, maybe even two or three. While working on a project with Sepp a couple of weeks ago in Germany he said something along the lines of receiving certification should really mean something, I think that's a big part of why I'm the only one who has received this honor from him to date, he's about as demanding and diligent a mentor as one could ask for, I wouldn't have it any other way.
Peter, I have a long standing policy of offering a discount for my first project on a new continent, Asia, Australia, and Antarctica are the only ones I have yet to work on. I would be thrilled to help you with your project.
Simone, I'm based out of Montana, very close to Alberta, and I'll be working in British Columbia this September and Saskatchewan next year. I would very much love to help you with your project as well.
If either of you would like to move forward with this you can find out more about my process and contact me through my website.
Based on the past several years I wanted to organize an expanded offering at the Krameterhof for English speakers to gain more hands-on practical experience with Holzer Permaculture. I think there is a tremendous amount to be gained form time observing and experiencing the Krameterhof as well. After talking it over in more detail with Josef we came up with an offering I'm really excited about.
This is going to be a very practice based workshop, come ready to get your hands and cloths dirty over an Intensive 10 days of Permaculture in Practice. We'll go over the Agroforestry systems at the Krameterhof, tap a spring for drinking water, harvest a pond, go over the aquaculture systems at the Krameterhof, Animal Husbandry and humane slaughter, Medicinal Herbs, Forest Gardening, Grafting onto wild fruits, Planning in Permaculture, modeling Water Gardens, and more. I can't express how excited I am for what I think people are going to gain from this opportunity.
Water Gardens at the Krameterhof
European Crawfish a very important and lucrative crop at the Krameterhof
Herb Garden at the Krameterhof
This is a Holzer Permaculture workshop all centered around working with the ecosystem of the farm. Participants will experience some of the inner workings of the Krameterhof; not just in theory but in practice so the body knows it as well as the mind and there is no hesitation for action.
In order to provide such a dynamic workshop we have to limit the number of participants to 25. As this is a first time offering, really the first of it's kind, I expect it to sell out fairly quickly. It's very reasonably priced at 1,120 Euros and right now the USD is particularly strong against the Euro. At the time of this post the workshop costs $1,215 USD.
Sepp has done an amazing job spreading the vision and strategy to establish these systems, he is the strong pioneer that creates opportunities for greater things. This will be the first opportunity for English speakers to really dive into working with ecosystems farming in an effective way on a long term established model landscape. With both the practice of establishment and then the development and harvesting of the ecosystem I feel we are preparing others to restore and regenerate landscapes as efficiently as possible - developing dynamic and synergistic ecosystems.
I'm so thankful for Sepp Holzer every day. When I think of what it means to be an Ecological Warrior, Sepp Holzer is the shining example that has inspired and empowered me and so many others. So much power, so much grace, so much wisdom.
I'm excited to again be offering the opportunity for English speakers to learn from and meet Sepp, visit his new farm the Holzerhof, and be the first group to see his new project in Jennersdorf. Participants will also have the opportunity to learn with several different students of Holzer visiting the first Edible Village in Austria the Wildniskulturhof located in the same region as Sepp's new place. Participants will also learn about natural beekeeping and log hives with a rebel beekeeper in the Austrian Alps.
We can only take 30 people for this event so be sure to register early to secure your spot. The early bird deadline is March 31.
Trip Highlights: The Holzerhof
The Edible Village of Ulbebach
This year's trip to Austria was an amazing experience for many different reasons, one of my favorites was being able to see a variety of different aged Holzer style systems in place. We saw the Krameterhof of course, an amazing demonstration of the possibilities to work with nature, the Holzerhof, perhaps even more impressive to see what can be done within 15 years and with virtually no maintenance for the first decade, and the Wildniskulturhof a project still within it's first year.
Judith has done a truly amazing job grabbing this project by the horns. What she has been able to accomplish within 9 months is remarkable Already a series of ponds have been created, a spring tapped, several shallow wells dug to harvest the ground water flowing through the property, a tiny home moved to the site, a few kilometers of terraces, an earth cellar, hundreds of trees planted, agro industrialized chickens renaturalized and given a much better life, and those are just the highlights. I'm further inspired as she provides an example of a single woman making all of this come together.
She has been putting her heart and soul into the project along with all of her financial resources and she has now come to a point where she needs to ask the community for help. Her goal is to get the remaining systems in place to support multiple people living on site to romance the systems that have been put in place to their full potential. This is after all the most important phase with Holzer Permaculture. This site will be an education center and demonstration site for other's to visit, work at and gain skills and experience to feel confident managing this type of system for themselves.
Unfortunately the video below is only in German but it still gives you a good idea of the scope of the project and the systems that have been put into place so far.
This video is also in German but is the most recent interview with Sepp. It really has some great content, maybe someone will be inspired to translate what he says and post it here for others to gain from as well.
About a week ago I became the first and only Certified Holzer Practitioner in North America. To the best of my knowledge I am the only person to receive this distinction outside of the formal training programs at the Krameterhof and in Russia.
Sepp is not an easy person to impress, it took over 10 successful Holzer style projects, lots of hard work, and plenty of gumption to finally receive this distinction; graduating summa cum laude with a degree in ecology was a breeze by comparison.
So what does this mean? I'm ready to facilitate an improved relationship between people and their landscape, I'm ready to play my part in the silent, peaceful revolution that's coming.
I give thanks to Sepp Holzer for the vision and tireless work he has done throughout his life; for blazing the trail that I now continue, for blasting through the wall that I now walk through.
You can send things freight freaky cheaply across country, especially if you ship from one loading dock to another (you can drop off and pick up from the shipping stations for the cheapest price). I sent 150 lbs of tools from Montana to Vermont for under $200 and that was having it delivered to a friends business which increased the price.
I am a permaculture consultant, designer, contractor, and educator working nationally, I would be happy to offer some workshops for your community. I have been working with notable Permaculturist Sepp Holzer for over three years now and am his leading student in North America (not my words but his). There is a wide variety of workshops I could offer within Holzer Permaculture and at this point feel comfortable teaching about most of his work.
I have also worked with and learned from many of the other top names in permaculture (Darren Doherty, Ben Falk, Michael Pilarski, and several others) and am very good at making sure I don't offend or put off anyone in my presentations and seminars.
You can find out more about my work at www.HolzerPermaculture.us www.ElementalEcosystems.com and www.PerpetualGreenGardens.com. I have worked and taught in a variety of climates, from Ecuador to the Yukon Territory and I would love to start spreading these techniques more in the Southern United States.
You can contact me via any of the websites listed above, it sounds like a great project your working on I would love to be able to help contribute to the work you are doing!
I am a permaculture consultant, designer, and contractor in Montana, earth powered greenhouses (ecosystem greenhouses that are beautiful and productive) are one of my specialties. I have been working with notable Permaculturist Sepp Holzer for over three years now, in addition to many of the other top names in permaculture (Darren Doherty, Ben Falk, Michael Pilarski, and several others).
You can find out more about my business at www.ElementalEcosystems.com and see some of the projects I have done. For my greenhouse business (addmidately outdated at this point) you can find more at www.PerpetualGreenGardens.com. I have been on the road for about 1 month working on projects from Southern California to the Yukon Territory and have 1 more month on the road before I'll be back in Montana. Once I am back I would be happy to help you with your project. You can contact me for more information via either of the websites listed above or in my signature below. Sounds like a great project your working on!
California desperately needs to re-hydrate the earthbody, not more false water management. A liner does not help re-hydrate the landscape, it only worsens the problem keeping the water separate from the land in an artificial structure. It may look prettier than a tank but a liner pond provides very little ecological benefit to the watershed.
Working with Time and Nature to Create Beauty and Abundance
May 1 – 3, 2015 at Sun Dappled Farms near Farmington, IL A Workshop with Zachary Weiss of Elemental Ecosystems
Zachary Weiss, a student of legendary Austrian Rebel Farmer Sepp Holzer, will lead a weekend workshop to inspire and empower participants to start creating their dream landscape. Having worked extensively with Holzer in both North America and Austria, Zach will share his unique approach to working with time and nature to create landscapes that are ecologically regenerative, economically viable, beautiful, and abundant. Water retention, Agro-Forestry, Animal Systems, Crater Gardens, Hugelkultur, Micro-Climates, and Earthworks will all be touched on during the workshop in addition to a variety of other topics. Zach is a consultant, contractor, and designer who also has extensive experience with greenhouses, natural building, and ecological entrepreneurship.
During the workshop Elemental Ecosystems will be creating a Hugelkultur bed and Natural Swimming Pool to improve the aesthetics and functionality of the area around the main house. Participants will have a chance to get their hands dirty, learning the real way to create, plant, and mulch a Hugelkultur while also learning how to cultivate water that is clear, healthy, and attractive. The natural swimming pool will be under construction during the workshop providing participants a unique opportunity to learn the nuts and bolts behind these systems, covering the important strategies and techniques for a successful project.
The Friday night lecture will cover Renaturing the Landscape: Sepp Holzer’s vision and strategy for regenerating the planet. This will provide participants an inside perspective to Sepp’s body of work as well as exposing people to the larger scale vision and strategy. Over the weekend participants will walk the landscape with Zach learning how to read and understand the different opportunities and possibilities that nature provides. Zach will paint the picture of the dreamscape that can exist at Sun Dappled Farms including ponds, Chinampas, and the integration of various tree and animal cropping systems.
Join us for an inspiring weekend with exquisite food from Sun Dappled Farms (we like lamb and duck!) and great discussion with others who are passionate about regenerating our landscape and working with nature to create paradise. The Friday Evening through Sunday Evening workshop costs $250. Meals and snacks will be provided. Housing in available via one of the farm’s lovely rentals for $40/night, $50 for couples. There is also plenty of free camping space available. Can’t stay for the whole weekend? Friday night’s lecture is free. To register for the workshop please email your intentions or questions to Kate Potter at email@example.com
Siu-yu Man, great question. I asked Sepp about this same idea and he did not think it was such a good plan. Krater Gardens are more intensive cultivation spaces where a lot of care and hand maintenance delivers the best result, not so much a space for raising pig forage and pigs. I thought it was a great idea to help seal the pond, but Sepp didn't think it was an appropriate technique.
That said pigs would be very easy to fence into this type of area. Just a single line of high voltage electrical line is enough for pigs. It is important that the pig is trained when young. The most full proof method I've heard is to train them with an electric fence inside of a real fence. Pigs are so sensitive with their nose that the fence delivers a shock they don't ever want to experience again.
A single line fairly low to the ground of high voltage electric fence should be plenty to keep them from running a-muck in the neighborhood. I've seen pigs even refuse to cross old fence-lines even after the fence has been moved because their memory is so good.
Elle, there are certainly benefits to small crater gardens, one huge one is as a model to gain an understanding of the concept and techniques to be applied on a larger scale. A vernal pool sounds like what you might be describing, which are valuable eco-tones, although not really a Krater Garden per say. The right approach really depends on the amount of water you receive, the time of year it is delivered, and the type of soil you have. Sometimes a vernal pool is a very appropriate solution as it provides valuable insect and amphibian habitat and helps retain water. For the real micro-climate benefits Sepp talks about with Krater Gardens they have to have significant climatic inertia and a lot of stone and water.
Greg Amos wrote: IMHO we should try to avoid putting dams in permanent creeks and rivers, as they can block wildlife.
I couldn't agree with you more Greg! Often times it is confusing for people when in "Desert of Paradise?" people see Sepp visiting a large reservoir and calling it an ecological catastrophe. The is the difference between decentralized natural water retention and man made reservoirs that actually steal the water from the surrounding land. With these Holzer style water retention areas the dam is made entirely of earth and the spillways does not impede wildlife, they actually enhance it similar to these waterfall swimming holes you shared. Most importantly the water is cycled by nature in accordance with her flows. These types of dams don't steal water, they just hold onto it for a little while.
A hydroelectric dam allows water to flood the creek when there is a need for power, not during the natural cycles. This can cause catastrophic damage for eggs and larvae of countless creek and river species. Not even to mention the need for fish ladders to even have a CHANCE of a wildlife corridor. And that is for the "Eco-Friendly" hydro-electric projects.
When I lived in Alaska I was quite near what was at one point the most productive river in the world. This was from the huge salmon spawns that used to travel the river each year. Today not a single salmon spawns up this river, with the city of Juneau built around it. Pretty surreal whenever I step back and think about that.
Greg Amos wrote: what could be the serious consequences?
If you are retaining a much large volume of water than the creek usually handles this much rushing down all at once can cause considerable damage downstream. Either via erosion, sediment flushing down the creek at an unusual time, or in the worst cases changes in stream course and catastrophic damage to downstream infrastructure. In Vermont one rain event cause millions and millions of dollars of damage because that large of an event had not been accounted for in much of the engineering.
Greg Amos wrote: the water stream after the earthworks would continue as before, just passing through a pond that was not there before
This is the ideal, nature always knows best and provides the answers to all questions.
Latin America is a stunningly beautiful place, sending my best to you down there!
When creating a Krater Garden you are expanding the exposed surface area of the earth; for the Sage Mountain Center Krater Garden we gained 400 square meters of surface area and it seems like even more than that. This means your growing surface has increased dramatically, as have the ecological niches. It's important that the interest, skill, resources, and availability of those invested in the project all coincide so that there is enough direction and guidance for the system to reach it's potential.
Cross section of the Krater Garden.
It's important that there is a surplus amount of water that is not currently being maximized that will feed this expanded surface area. You need to know what your runoff coefficient is, if you have overland flow, and the size of the area feeding the given point. Then the 24 hour and 36 hour 100 year rain event figures and accommodate for an even more catastrophic event with the hydro-logical plan. It is also important to have an idea of what your evaporation rates are. I think I'm safe in saying that every Krater Garden should have at least a vernal pool in the bottom. If you have enough water for even larger cultures then this would be a higher return solution.
There are specific features within the landscape where a crater garden makes sense, where the landscape lends itself to this kind of treatment. Everywhere but these given features there are more effective treatments that can be done. Often times in places where a Krater Garden would make sense the area can be more effectively cultivated with more water as part of an aquaculture system with large ponds and Chinampas; more intensive aquaculture systems would provide an even greater return on investment.
Artist rendition of the Aztec Capital of Tenochtitlan. It is thought that 1/2 - 2/3 of the food eaten in the city was provided by Chinampa.
It's amazing how many of the great cultures of days past had great reverence for water and skill working with it in a variety of ways.
Here is a video of Peter McCoy from Radical Mycology talking about how he trained fungi to digest used cigarette filters. Seems like a very cool way to partner with fungi to help start remediating our environment.
Peter is one of the core educators for the Ecological Living Summit this summer in Montana. He is going to be teaching a variety of workshops including:
- Medicinal and Ethno-Mycology
- Cheap Spawn Production for Mushroom Cultivation
- Aseptic Lab Work
- Mushroom Identification
- Mycorrhizal Fungi
For more you can visit the permies thread about the summit by Clicking Here
Nick Kitchener wrote:Come the dry summer months, wouldn't that mean less evaporation due to the reduced surface area
Swales increase the surface area of soil exposed to air, so all other conditions being equal this would actually increase evaporation during summer months.
Nick Kitchener wrote:He mentioned that his soil never saturates. If that is the case then is he getting no movement of water through his land?
My understanding of this is that he that he means his soil never saturates to the point where there is surface runoff; water is still moving through the soil, just not over the surface. In a very specific situation where there is an impermeable clay layer right at swale depth or a bit above, the swales would act in the way you described even without surface runoff. Without this very specific geological condition though there would be nothing I can see keeping the water high enough in the soil to actually enter the swale system.
Great question, this one really made me think. This seems like a good technique to make a swimming hole, but I wouldn't really consider it a pond per say. A couple of thoughts.
From my training with Sepp I have been trained to be wary of any wood, debris, or roots being accidentally incorporated into a dam, as these will provide eventual failure points moving forward. That said for this type of swimming hole you are not creating a dam but rather a water fall that creates a swimming hole; I like the strategy if your primary goal is to make a deeper section in a creek to plunge into. It is also certainly great habitat as the article mentioned. This seems appropriate for swimming holes but I wouldn't consider this technique for a large pond with potentially serious consequences in the event of a failure. Here are my only concerns.
I would NOT use galvanized anything in a creek. It is pretty toxic stuff and I would never knowingly incorporate that into a stream system. But I am a purist when it comes to this type of thing.
I've heard that wood will not rot so long as it is constantly submerged in water. As there would be ample time when the top log is exposed to air it seems like this system would eventually fail over time. That said this could be a very long time with a species like black locust and the ramifications would not be too severe as you are talking about pretty small changes and a small amount of water being held behind this structure.
With this method don't you want erosion where the water enters the "pond." My understanding from the article is that this is the force you are using to make the deeper pool within the creek. Spillways armored with rock and replicating a stream bed is the best way to mitigate erosion that I know of.
It is important that you do calculations for the watershed of the creek to understand the water potential for the 24 and 36 hour 100 year rain event and feel confident that your system can handle the water from an even larger rain event. If I were in your shoes I would create a Holzer style water retention area with a keyway dam as this is what I understand will lead to the greatest benefit for the surrounding ecosystem. You will save many years of work on your back's sake with one day with an excavator. And when it comes down to it even if you only value your time at $10 an hour you will save a boatload of money by calling in the big guns for the heavy work. That's my 2 cents.
Sounds like a beautiful spot you guys have to steward, best of luck with this project!
I am not sure what the insulation for the wall is, I believe the door is EPS but I'm not positive about that either. Staw bale insulation would certainly work so long as you manage the permeability of the plasters appropriately. The interior plaster should be less permeable than the exterior plaster. This way the staw bales are always balancing to the outside moisture content rather than the high humidity inside the cellar.
For the log cabin style root cellar they actually use timbers, or slabs milled flat on two sides. With this technique the timbers fit together perfectly and there is no need for mortar. This style is for a very sealed structure that would be used for a permanent root cellar. The vertical arrangement is easier to build, and un-milled logs are used so they require less tools and time. They each have their benefits and appropriate times of use. As stated before the vertical arrangement is predominantly for earth stables and the horizontal style for root cellars.
With these two pictures you can see more of the differences between the two different types of earth integrated structures. Below is a shot of the interior of the timber, log cabin style earth cellar.
And here is a picture of the vertical log style earth stable.
Paul Ladendorf wrote:what you said about "not enough sun to grow anything in the winter" seems to be fairly controversial. Do you say that based on experience?
This depends on where you are and what you want to grow. Lots of perennial crops you might want to keep a greenhouse warm for require minimum daylight hours during the winter in order to fruit. This means that even if you can keep your greenhouse warm enough these types of crops won't produce fruit without supplemental light. Other crops may grow in the winter but will not be anything close to their full potential under such conditions.
Eliot Coleman has got some great stuff with greenhouses and I use his 4-season gardening techniques often and recommend them to clients. Just to be clear it is a 4-season harvest system, growing cold hearty crops with the last sun of fall and then storing the crops alive in the greenhouse and harvesting throughout the winter. I am eating a salad as we speak grown this way and the greens and more sweet and succulent than at any other time of year. Once you get a taste for this you will realize many types of greens and root crops are the highest quality during the winter.
I've seen tomatoes grown in cloudy northern climates but they have always involved grow lights and they don't taste very good. If you want great tasting tomatoes in the winter the best strategy would be to grown a surplus in the summer and can them. The white tasteless tomatoes you kind find in the store during the winter, this is the reality of winter sunlight ripen tomatoes, there just isn't enough sun for the fruit to develop it's full sweetness and flavor. If your main goal is to grow tomatoes in winter without supplemental light I would recommend putting your resources into a more fruitful project.
I use the 4" pipe so there is maximum temperature transfer, for larger diameter you need longer runs. The cfm and length of tubes really depends on your cooling load during the summer. You will most certainly need additional ventilation as well. Do you plan to use shade cloth? Lots of variables here. Best of luck with your project!!
Unfortunately I have yet to find any good sources for clear information on earth tubes and I have been looking for years. General rules of thumb seems to be about as good as it gets. From my understanding and in my work it is VERY important that you use perforated tubing. Anytime warm humid air comes in contact with a cold surface it will condense moisture, regardless of if it is corrugated or not. The primary function for the corrugation is to slow the air down as it passes through the tube enabling more temperature exchange.
I would be very cautious about going down into the water table, one small hole in the tubing could render the whole system useless as it fills with water. I have not heard before that HDPE will not grow mold but this is what I am always sure to use within my own projects. At first impression I would be VERY wary of this company, moving warm humid air through a cool environment without condensation seems to defy the laws of physics as I understand them. Not saying it's impossible but I would be wary for sure.
So put me in the camp of only using perforated, corrugated, HDPE tubing and don't go down into the water table. I have been installing earth tubes in greenhouses for clients for over 4 years now making sure to use this type of tubing and have yet to run into any issues with mold. I have heard disaster stories of people using solid tubing, and with the corrugations you would not have any way to clean this type of tubing, meaning there wouldn't even be a labor intensive fix if mold is an issue.
1. Yes I have seen mold issues, and it has always been with solid tubing. Solid tubing can be used so long as it pitches to daylight, but this is only possible in very specific situations.
2. If the tubing is in flowing ground water then this will carry all of the heat you are trying to store down hill.
3. I wouldn't expect any noticeable cooling of the ground temperature, although this setup could be used to help cool the air that you are blowing through the tubing.
4. This totally depends on the context of where you are. In many cold climates even if you can keep the greenhouse 50 degrees there isn't enough sun to grow anything. Often times it is better to run a short dormancy to work with the natural cycles for healthier plants and less pest troubles.
5. I base all of this on the cu ft of air volume that I need to move in the summer to cool the greenhouse, then design the system based on this calculation.
6. Rules of thumb is about as good as it gets, at least from what I've come across.
7. I have never insulated below the tubes, but I also build earth sheltered greenhouses that function depends on receiving the ground temperature to help balance out the extremes. 20 degrees sounds like a huge differential, I would expect more in the 5-10 degree range.
Yes the doors are both sealed very well and insulated in order to keep the cellar stable at earth temperature (4.5 degrees C at the Krameterhof or your mean annual temperature for a given location) and to keep critters out. These cellars look like they are built to last, I would expect 50 or more years of use.
I have my first root cellar in the schedule for once the weather warms up a bit. Below is a picture of the new kind of root cellars Josef has been building at the Krameterhof. The one that I will build for a client this spring will be this style. So I have not built one myself yet but I have seen several different types and through multiple workshops with Sepp understand the process well. I will also be teaching a workshop on Holzer style earth stables later this year in Wisconsin.
These are made with timbers stacked similarly to a log house and then lined with EPDM pond liner and a dimple shield membrane. This style is used predominantly as a root cellar.
Below are two pictures of the log style that are a bit quicker and cheaper to build and typically used as earth stables. These are both 10 years old and it was clear that they will last for several more decades while I was there visiting.
It is very important to note that Sepp is only using very rot resistant species such as Black Locust and Larch, this is the primary reason that these earth stables last so long. I would expect a structure like this to last around 50 years, potentially much longer in drier climates.