Three Sisters Permaculture Farm

Darrell Frey talks about permaculture farming, the danger of GMOs and how to choose the best local, seasonal foods.

Darrell Frey is the author of Bioshelter Market Garden and farmer/owner of Three Sisters Farm in Pennsylvania, which provides fresh, organic produce to the local foodshed, even in the cold winter months.

Frey’s initial interest in homesteading and self-sufficiency led him to a study of permaculture design.  In 1983, he and his wife, Linda, bought a 5 acre parcel of land in Sandy Lake, Pennsylvania.

It was good farm land, but the soil had been ruined from decades of conventional farming practices. The Freys put their years of permaculture study to practical use regenerating the soil.  In 1988, inspired by the work at the New Alchemy Institute, they built a bioshelter.

The two story bioshelter is the heart of the farm, and integrates around 3,000 sq ft (278 sq m) of growing beds and cold frames, a packing shed, potting room, office, classroom space, kitchen, compost bin and a chicken coop.  It also serves as a warm and sheltered environment to get a head start on seedlings in the bracing Pennsylvania winters.

In his book, Frey describes bioshelters as “wholesome, biologically rich corridors between the wild and the cultivated, linking natural and man-made environments.” Unlike ordinary greenhouses, bioshelters are carefully designed and managed ecosystems.

Every greenhouse environment needs to integrate temperature controls, and heating a greenhouse for four season growing in cold winter environments can be prohibitively expensive.  Permaculture design employs careful observation and understanding of all available elements in a system, and seeks to integrate multiple elements to satisfy each requirement.

In Frey’s case, the meticulous design of every aspect of the building itself provided many solutions to managing the variations between cold, dark winters and hot summer sun. Placing the kitchen and storage areas on the north side of the structure provides protection from winter winds, as well as cooling ventilation in the summer.

The bioshelter was designed to the exact arc of the sun. The glazing angles were devised to capture the maximum amount of solar gain during the winter and early spring, when the sun is low on the horizon, while strategically shading the interior in the summer and autumn.

Getting solar heat into the greenhouse is one aspect of passive solar, but keeping it there requires storage.  Frey’s bioshelter stores heat in several kinds of thermal mass—such as rock, soil, water tanks and block walls—which absorb the heat and then release it slowly into the air over long periods of time. This helps to distribute heat and stabilize temperatures after sunset.

Unlike most greenhouses, the Three Sisters bioshelter utilizes extra deep growing beds, with the bottom layer of the beds consisting of 30 tons of rocks.  The ventilation system passes warm air from the compost bin and the body heat generated by the chickens over the rocks, which absorb the heat and release it slowly under the growing beds, keeping the soil warm.

A wood heated water tank and cast iron stove supplement the solar and biothermal heat in the dead of winter, when the night temperatures drop below freezing.   An exhaust fan, roof vents and strategically placed windows keep the bioshelter from overheating in the summer.

The result of all this detailed evaluation and design is a greenhouse that produces organic food all year long with very low heating costs.  Frey estimates the bioshelter uses 3 chords of wood to get through the coldest months.  The thorough and efficient integration of natural existing resources is a feature of many permaculture designs—as is the tendency to favor detailed yet simple design over high tech or non-renewable energy solutions.

Three Sisters Farm is not only a market garden, but also a teaching center.  Everything from weekend workshops on grafting to two week intensive permaculture design certificate courses are offered there.

What is a permaculture farm, and how is it different from a certified organic farm?

A permaculture farm is simply a farm that is designed and managed using permaculture principles and practices. Permaculture design has core ethics of care of people, care of the earth and fair sharing of excess.

It certainly begins with organic practices but may go beyond these to include goals of building community, increased biodiversity, energy efficiency, reduced carbon foot print and reduced environmental impact. In fact, a permaculture farm strives to have a positive impact on local and global ecosystems through environmentally conscious choices.

Additionally, the permaculture farm strives to be a positive part of local and regional culture, working towards more environmentally and socially equitable bioregional communities

At the heart of Three Sisters Farm is a bioshelter ecosystem. Tell us what that is and what that means for feeding people in cold winter regions. Is it different from a greenhouse? I’ve heard that greenhouses can have problems over time because soil really does benefit from being completely open to the air and sun to prevent disease or pests. How do you deal with these issues in your bioshelter?

I define a bioshelter as a solar greenhouse managed as an indoor ecosystem. Habitat is provided for beneficial insects year round. A wide range of crop plants may be included. It is a human managed ecosystem, but not a closed system. Our bioshelter is integrated with the surrounding landscape to allow ventilation, and the movement of beneficial insects between the bioshelter and adjoining gardens. We have had minimal disease problems in 24 years of operation. Diseased plants are removed and composted, or fed to chickens.

A bioshelter is one of several tools for year-round food production in cold climates. Poly tunnels—both low tunnels and high tunnels—and cold frames are generally unheated structures that help extend the growing season several weeks or more in the spring and fall. Our bioshelter, with solar and wood heat, is a frost-free zone and allows the production of a wide range of herbs, edible flowers, salad greens and cooking greens. When days are sunny, even in mid winter, plants grow.

Our own location gets a lot of clouds between December 1st and Jan 15th, but after that we have good production all winter.  Greens such as mustard, kale, collards, tatsoi, mizuna, lettuces,  parsley, leaf celery, nasturtium, spinach, beet greens and many other salad greens produce abundantly.  Herbs such as thyme, oregano, bay, and rosemary also produce well.

And of course, our bioshelter is used to propagate thousands of cuttings and seedlings each year for our gardens and for sale.

We believe that any community can benefit from a bioshelter, not only for food production, but for the educational value and therapeutic value of being in an edible conservatory. As we continue to develop stronger local food systems, bioshelters will be a key strategy for food production in the sustainable society.

When you bought the 5 acres that is now Three Sisters Farm, the land was depleted of life and nutrients due to decades of conventional agricultural practices. How long did it take to return the soil to fertility, and how did you accomplish this?

First we left the land fallow for about 5 years and allowed selfseeded accumulator plants and biennial tap rooted plants to move about the field to renew minerals and break up plow pan. These included Queen Anne’s Lace, various docks, yarrow, wild brassicas and numerous others.

Then we planted mixed clover and alfalfa for several years to add nitrogen. These legumes naturalized in various locations in the landscape. Red clover, white clover, black medic—all found their niche and persist through self seeding.

Finally we began, and continue, a process of mineralization as needed with soil amendments, and with the addition of composted manures as needed to build and maintain fertility.

Crops are rotated in various ways to make the most of added nutrients: organic mulches, straw, hay, sawdust, shredded mulch.

One of your strategies was to grow slowly, adding and expanding only when you could commit the time, focus and money to do so. This is quite contrary to what most farmers do, which is borrow large sums of money for seeds, equipment and structures, then grow as much as possible in order to keep ahead of the debt. This crushing debt makes many farmers extremely vulnerable. In what ways has your slow growth, low debt strategy worked for you? What has it allowed you to do that you wouldn’t have otherwise been able to do or try, if you had a large debt burden? What are the downsides to this approach?

We did occasionally borrow from our local bank, but kept the loans small and manageable. This does make the development of new enterprises slower, but helps us keep focused on tasks that are priorities, such as crop production and marketing of our produce, plants and herbs. New enterprises are developed with partners who invest their time and labor for profit sharing ventures.

People argue that the slow, thoughtful approach of alternative farming methods, such as those that adhere to permaculture principles, constitute ’boutique’ farming and are not productive enough to feed the world. What would you say to those who feel that your approach is a personal philosophy as opposed to a farming method that can be relied upon to feed the growing population?

Specialty crop farming can keep farmers on the land and keep them producing. A wide range of specialty farms make a region vibrant and enhances local culture. Small scale intensive agriculture fed China sustainably for 4000 years ( except perhaps in times of war or natural disaster). There is a need for many scales of agriculture in regional food systems, but one really does not need to feed the world.

Most food shortages around the world result from political conflicts and from the fact that many peasant farmers have been forced off their land by multinational monoculture interests claiming to feed the world. Certainly there is a need to have excess staples to aid those struggling in times of drought, war and natural disasters—but a return to regionally self sufficient food systems, with a reasonable amount of ethical trade, is what is needed to feed the world.

One of the principles used in permaculture is stacking functions. Can you explain what that means and give an example of how you do this in your bioshelter?

Stacking functions is a way to save time and energy though good planning and design. When driving off farm to make deliveries we also try to schedule shopping for supplies, meetings, consultation and other activities. Planting trees and shrubs in configurations that provide windbreak, privacy, microclimate enhancement, prevent erosion and nutrient loss, and promote biodiversity is another example.

Permaculture offers a deeply sensible approach to designing and running a farm, but one of the really interesting things about permaculture is that its principles can be applied to many areas of life. It seems to be a very sane meta-strategy. How has your experience with permaculture informed other parts of your life?

Really the essence of permaculture is to recognize that everything exists in community and in relationship to everything else. Finding positive feedback connections between elements in a design or activities and people in your life can lead to stronger community and new activities that reinforce the feed back to keep landscapes and ourselves sane and healthy.

Farms are typically not healthful places to live. Agricultural areas are often similar to heavy industry zones, with attending issues of air and water pollution, noxious odors, etc. Do you live at Three Sisters Farm, and if so, what is it like?

Wow, that statement is sad, though perhaps often true. I do live at the farm, and (other than some of our cluttered storage areas) it is an incredibly beautiful place full of bird song, fragrant flowers, tasty fruit, the laughter of my granddaughter and friends, and the the buzz of bees and chirping of frogs and night insects. The farm is alive with myriad neighbor creatures all adding to the the rich tapestry of our farm.

Bioshelter ChickensBioshelter From The PondPromoting Diversity On A Permaculture Farm

Three Sisters is certified organic. What do you think about organic certification? What do you see for the future of organics?

The term ‘organic’ has become a minimal threshold for entry into a lucrative market, and requires vigilance on the part of farmers and consumers to maintain the integrity of the term. It is intended to be a high standard of soil and land management. We are currently not certified organic, but may perhaps be so again soon.

Currently we have chosen to not certify our farm as organic because our customers do not require it and they understand our commitment to sustainable, regenerative and organic agriculture. When we someday phase in value added products or seek new markets we may again certify.

What should people look for when evaluating what to buy and where to buy it?

People need access to fresh food, which means local, and seasonal foods.

  • Grow your own as much as possible.
  • Buy what you can not grow from someone you can get to know, and visit the farm and even participate in the production of natural and organic food.
  • Support the larger organic and fair trade movement with any purchases

Really many people’s perceptions are changing. People everywhere understand the need for fresh food.They need to understand that the farmer needs a reasonable profit to continue to provide that fresh food.

Perhaps they need to better understand the need for stewardship of soil, water and land. People also need to know that the energy and intent of the farmer comes through to them as they eat. The ethical treatment of the plants, animals, land and the planet affects us all. The health and well being of everyone is rooted in our relationship to each other, the land and all our relations.

Anyone who makes a concerted effort to buy ethically produced food will tell you—it’s expensive.  Some of it is really expensive.  If small, responsible farmers are working really hard to make a decent living,  while people who are committed to buying the best food are staggering under their grocery bills…how do we make it work?

There is not only one easy answer, I am sure. Family income from the farm relates to many concerns.   The cost of health care, education debt,  and maintaining a reasonable lifestyle all  can make it difficult to for a farmer to succeed solely on farm generated income.

So the farmer strives, as any business, to develop the most lucrative market for preferred crops. Value added enterprises and urban restaurants are among the best markets for the innovative farmer. These markets can drive up prices for household consumers but they also promote regional food culture and food systems transition.

Since I began market gardening, I have witnessed the emergence of many dozen regional farms in western Pennsylvania. My expectation is, as small scale local farms continue to increase in number and diversity, the cost of organic products and income potential for farmers can achieve a good balance.

Many of these farms will remain seasonal  or only provide part time income. But local organic food is becoming more plentiful, and I expect, more affordable.

If you could change one thing right now to make sustainable food more available, what would that be?

I would make the word ‘sustainable’ synonymous with truly organic practices. The word sustainable has been co-opted for decades. Many in permaculture prefer to use the term ‘regenerative’ to illustrate our goals.

The greatest challenge to our planet is the release of genetically modified organisms into the natural world, followed by climate change and then the toxic chemicals released into the natural world. The challenge to sustainable agriculture is to recognize these facts and become truly organic, on a human scale.

photo credits: Elizabeth Lynch, Leo Glen

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  1. I only just fond your web sight and this article was so inspiring for me to read on how your farming in Pa. I’m an older women who grew up with gardening for the family and the old peoples ways of food homemade breads, canning ect. I lost my growing and canning for the convenice of grocery stores which have changed so, we could shop everyday meats, veg ect and not a mile away from home, and fresh eggs. Food have changed since I have growen a tomato is not the tomatos I used to pick and have a small salt shaker in my pocket and eat like an apple, wonderful. Since food now have so many chem and what else they do to seed I want to start and grow my own if I can manage at this stage in my life. Your article was wonderful for me with hope there are people who want Mother Earth to get back where she should be.
    Thank you so for all your doing,

    • Hi Linda,

      Thanks for your kind words, and I’m glad you were inspired by the work that Mr. Frey is doing on his permaculture farm.

      I couldn’t agree with you more about how food has changed over the years. Supermarket produce is a far cry from my mother’s kitchen garden. But it’s important to know that there are many small, local producers and farmers who are getting back to real food, produced in ways that add to the fertility of the land and environment. They deserve our admiration and support.

      I wish you the best of luck with your own food garden. Growing food is not just good for your body and cheaper, but, in my experience, brings a deeper sense of appreciation, even awe, to the food we eat.

      Be healthy, stay positive, and share what you learn with friends and family.

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