Creating a Home Ecosystem with Permaculture
by Toby Hemenway
Toby Hemenway was a permaculture author and design teacher who passed away in 2016. His intelligence and ability to synthesize and express the ethos as well as the practical skills of Permaculture are brilliantly on display in his book Gaia’s Garden: A Guide to Home-Scale Permaculture, one of the best-selling permaculture book of all time and an essential operating manual for the beginner as well as the seasoned practitioner. This is an edited excerpt from a presentation Toby gave at a Bioneers conference.
It’s interesting that humans, being tool-using, thinking animals, have only recently, at least in our culture, been thinking about what design really is. How do you design things in an intelligent way? Where’s the instruction book for good design? To answer that question, more and more people are turning to nature for those instructions and trying to preserve the parts of nature that are still intact so that we can learn from them.
I did environmental work for a while but found it depressing to be constantly in reaction to the destructive forces, but when I learned about permaculture, I was encouraged by its proactive design principles.
Permaculture was started by Bill Mollison, a wild Australian, who had worked at a variety of jobs: ecologist, trapper, instructor at a girls’ school, etc. While working in forestry in Tasmania in the 1950s he observed the ecosystem around him and was struck by the question: “Why can’t humans design environments that are as resilient, as productive, and as stable as those in nature.” He spent the next 20 years working with a student of his named David Holmgren to extract the principles from nature that generate fertility, resilience and long-term ecological health.
If you go into a forest and observe how it’s working and return three months later, even after a drought, that forest will still be in good shape. But if you go on vacation for three months and come back to your yard or garden, it’s a whole different story. Everything’s dead or overgrown. What is it that nature, left to its own devices, does right?
Often in modern society, when something is built, there is a net loss to the environment. It usually winds up creating a lot of pollution, waste and energy use. There’s got to be a better way. In permaculture when we’re building something, one of the first things we do is ask questions. What are the things we’re trying to achieve? What are the big objectives? When humans go into cities or anywhere else to live, what do we need to look at? And what are the main effects and problems of the project?
The things that we usually look at as problems are: excessive energy consumption and water use, and the production of waste. When humans build structures, they often build impermeable surfaces around them. As a result, rainwater does not percolate into the ground the way it should, and on the north side of buildings, at least in the northern hemisphere, it’s hard to grow anything because of the shade. These are some of the things that could be considered problems, but in permaculture, we like to think of the problem as containing the seeds of its own solution. The mantra is “The problem is the solution.”
When you put up a building, you’ve got a big roof area that can collect water and you can also put solar panels on it. That way, the building, instead of just using energy and water, can also supply some of its own resources.
Most of us are packrats. We’re always bringing things on site. The idea is to try to reuse materials rather than using them in a linear cycle in which things are thrown away when you’re done with them. Organic “waste” can be made into compost. Discarded items can be reused to build graywater systems to harvest wastewater for a second use. The nutrients in the waste water, such as nitrogen and phosphorous, are good for the garden.
The south side of a building is warmer than the other sides and is going to collect heat. Observe where the shady areas, the areas protected from the wind, the drier areas and the wetter areas are. Around the structure, there will be a number of microclimates; how can we use them appropriately? Drought-tolerant plants can be placed in the dry areas. Bog plants are the obvious solution for wet parts of your yard, etc.
Ecotones are areas where two biological communities or ecosystems meet. Interesting things happen in these edges. Where a forest meets a prairie, for example, there will be forest species and prairie species, but also species that are unique to that edge environment. Edges are the places of maximum diversity. Human beings unintentionally create a lot of edge. Deer like the open forest edge. If you look at suburbs, there are often large deer populations because deer love those divided up edges typical of suburbs. Edges are places where things are translated and accumulate. If you put up a fence, things that blow up against it can be harvested and used.
In suburban communities, the plant diversity can be astounding, as people bring in their favorite plants from all over. Sure, you’ll find some sterile places in the suburbs that just have rhododendrons, but often, if you walk around in a suburban neighborhood noticing plants, you’re probably going to see greater plant biodiversity than there was in the original, natural ecosystem. It’s not true everywhere, but people bring in hundreds if not thousands of plant species into the places humans inhabit. People do create biodiversity, though I’m not making a value judgement about whether those non-native plants are good or bad. But it does imply that humans, with the right approach, can become stewards and can be a net asset to a place rather than the usual liability.
Another concept in permaculture is the idea of zones or relative location. It’s about putting things in the right place. Think about the specific needs of plants and how often you need to take care of them, and then put them in the location that’s most appropriate. Plants that you use the most or that need the most care go closest to the house. It’s rather simple, but often people don’t think about those things. You don’t want to put plants that need a lot of water far away so you have to drag a hose to them, that would be a better place for desert or drought tolerant plants.
Mary Zeemak lives in Los Alamos, NM, at 7,000 feet in the high desert that gets only 14 to 16 inches of rainfall a year. It’s a really severe regime. It gets bitterly cold in the winter, and in spring and fall the temperature swings can be enormous from day to night. And in the summer, it gets very hot. It’s a harsh environment to be gardening in, and the main concern there is water conservation.
Her water supply comes from some deep wells that the Army Corps of Engineers drilled, and it’s expensive: you can spend $300 a month watering your yard if you have a conventional lawn. Mary took a permaculture course from the brilliant designer Ben Haggard and has installed a permaculture garden on her property. She has eliminated the need to use municipal water for the most part in her yard. She waters about every three months, and this in an area with only 16 inches of annual rain!
How does she do it? She uses a set of strategies, one of which is to contour the land to hold water. She dug depressions or swales next to her sidewalk. You can think of it as a long, skinny, pond. It’s just a few inches deep and of couple feet wide, big enough to capture all the runoff water from the sidewalk and infiltrate into the soil. She contoured the land so it will hold water and deliver it to where she wants it. The downspouts from the house are directed into other little swales that take the water to the plants that need it.
Swales are a fantastic way of infiltrating water into the soil. Once the water is in the soil, it slowly migrates downhill from your swale. The underground water is held together by hydrostatic tension. It’s like a little underground lake, and all the plants below your swale stay green longer into the dry season.
Her neighbor uses a typical overhead sprinkler that goes on late at night, so Mary dug a little swale right around the edge of her yard to capture the overspray. She’s not stealing the water; she’s just making the best use of this resource.
The permaculture principle that Mary employed is that each important function should be served by multiple elements. It basically means that you should build in redundancy. You should have fail-safes and back-ups. Nature never does an important thing with just one method. Nature always has multiple back-up systems or redundancies in place. Water conservation is an important function, so you want several different strategies to accomplish that. Mary has five water conservation strategies.
As I mentioned, the first strategy is contouring the land to hold water. The second one is increasing the organic matter in the soil. Mary had a conventional lawn that she sheet-composted. She added lots of organic matter because it holds water in the soil.
The third strategy is to mulch everywhere. One of the hallmarks of a permaculture landscape is a big mulch pile next to the house with mulch on everything. Mulch protects the soil from drying out. It keeps the roots of plants cooler so they’re not transpiring as much water. It’s a great way to conserve water.
People ask me, “Don’t you have a terrible slug problem with mulch?” I’ve found that I have fewer slugs in my yard with mulching because it’s also great slug predator habitat. Garter snakes like slugs. There’s a predacious beetle that really likes slugs. There are a lot of insects that occur in the mulch, so birds come in and start picking through it and they find the slugs and pull them out of it. If you don’t have mulch, you only have slugs, but if you have mulch, you’ve got slug predators that bring down the slug populations.
The next strategy is to have dense plantings so sunlight doesn’t fall in between the plants. Dense plantings shade the soil and reduce evaporation. Mary planted 1300 plants in her one-third-acre yard, and most of them have survived.
The next strategy is to put plants in the right place. The hard and fast rule for water conservation is to use only drought tolerant plants, but each situation is different. Consider what is appropriate for a specific spot. In the places that have water– near downspouts, or near water faucets or water collection tanks – are where you should put plants that need the most water. Out by the street is where the native and drought-adapted plants should go.
The five strategies – contouring, building soil organic matter, dense plantings, mulch, and the right plants in the right places – all work together in support of water conservation. In that way, if one of the strategies fails, for example if during a windstorm all the mulch blows away, those other strategies still conserve water. Mary is able to go away for three months in between waterings, even with very little rainfall.
The other benefit of multiple strategies that support an important function is that synergies can occur. When we build up organic matter to hold water, we’re also building the fertility in the soil. When we add mulch to the soil, it breaks down and also creates additional fertility. Serving important functions, such as water conservation, with multiple elements that have several advantages is how nature works.
There are other permaculture principles that use nature as their model. Diversity is one of them. Mary’s yard is full of tremendous diversity: Echinacea, a peach tree, Joe Pye weed, lots of salad greens and edibles. She lives on a north facing slope, which is a gardener’s nightmare. It’s dry and shady, but she’s managed to grow a tremendously productive garden with lot of biodiversity.
Mary raised a family with her husband and they had a four-car driveway. There was lots of concrete that they wanted to get rid of and turn the space into a productive growing area, so they had most of the concrete driveway dug up. The permaculture designer that they worked with said, “You know we have to keep all this concrete. You have to be as responsible onsite for our own waste as you can be.” He proposed that they make terraces out of it. “Urbanite” is what permaculturists call broken-up concrete. It’s a rich mineral resource in cities.
But Mary wasn’t really wild about the idea of broken concrete chunks in her yard; it didn’t fit with the upper middle-class image of the area, but the designer did a demonstration bed that she absolutely loved. The terraces are now completely overgrown with plants. You can’t even tell that it’s concrete. She loved it so much that after they used all their own concrete, they went to the dump and gathered another 40 tons of concrete and brought it back and re-did the whole yard in “urbanite” terraces.
Down from her backyard is a ravine full of piñon pine and juniper trees; she’s gardened part of the way down but left the rest as a wilderness area. This is where the native birds, insects and plants are. Mary can go down there and observe and learn from them and bring those teachings back into her yard.
Up from the ravine the soil is not very good. Instead of importing a lot of materials to build soil and working only on that one task, she has constructed a straw-bale greenhouse. The inside is hollow. You put hoops and greenhouse plastic over the straw-bales and put your plants inside. After two or three years, the straw-bales mulch down and you have a foot of beautiful soil without having to do the work of building the soil. You just let the natural organisms do the work for you. While you are using the greenhouse, you’re also building soil. Then you bring in new strawbales and build another greenhouse in another place.
Mary and her family like to entertain, so she needed a little social space in the backyard. They have a little patio and a small lawn, the only lawn on the property. They planted buffalo grass, which is drought-tolerant and grows very slowly. You hardly need to water or mow it, so it’s much less resource-intensive than Kentucky bluegrass and other common lawn grasses. The lawn area is dished in the middle, shaped to hold water. It’s about four inches lower in the center than it is on the edges, so when it rains, the water pools there and soaks into the soil and it doesn’t run off.
In the past, fires in Los Alamos have run through the ravines. In addition to being a social space, the lawn area is also a fire break. It’s a big enough opening so, in any but the most catastrophic fires, it’s probably going to stop fire from coming from that arroyo to her house.
The principle that this illustrates, which is the converse of the earlier principle that every important function is served by multiple elements, is that every element should serve multiple functions. Everything you have in your design should be doing more than one thing. In this case the social space is also a fire break and also captures water.
When conventional landscape designers plant a tree, they usually think of it in terms of creating shade in one spot, or providing fruit, or having pretty pink blossoms in the spring. They think in terms of one function for that tree. But a tree in nature is creating shade, food and beauty all at the same time. Its leaves are picking up pollen and dust from the air. It’s harvesting rainwater. It’s breaking up soil with its roots. It’s adding organic matter. The list of its functions goes on and on. It’s doing many things at once.
Intelligent, creative designers make sure that elements in their designs serve at least two and preferably three or four functions. Doing that connects your landscape together. If you have plants that provide habitat, then you’re connecting to the birds and the insects. If you have a downspout connected to a little pond or to an irrigation system, you have connected your structure to your gardens. Connecting pieces together is “whole-systems” landscaping.
Using these permaculture principles (as well as others) to develop intelligent design you can take care of some of your own needs and reduce your ecological footprint while you generate habitat, conserve water, conserve energy, grow food, and have a beautiful place.