Permaculture is described as a low impact method which uses perennial cultivation methods to produce food crops in harmony with nature. This might sound a bit "new age", but since much of the energy used in mechanised agriculture is to drive processes that restrain the land from returning to its natural wilderness, if productive agriculture can be had at a minimum of this energy input it is a much more efficient and "natural" way forward. Certainly in developed nations, food is not grown locally but must be brought in from surrounding regions, or much of it imported globally. The monoculture system that is typical of modern farms drains nutrients from the land, which is fed with artificial fertilizers, and many of the natural flora and fauna no longer exist.
Such single crops are vulnerable to pests and diseases: for example, the Irish potato famine was a result of Blight disease which rapidly devastated the single species of potato which was being grown at the time and was the staple food for the poor. Previous generations grew cereal crops but since the potato was more robust to changes in the weather and produced about four times as much food per hectare, it became the crop of choice. Production of 'biofuels' is diverting more land to the growth of monoculture crops, and along with the eradication of vast swathes of rainforest, is far less 'green' as a fossil-fuel alternative than is frequently claimed. The necessary competition between growing crops to feed humans and animals or cars has also driven-up the price of staple foods like wheat and corn.
The permaculture approach resonates philosophically with the Gaia hypothesis, first voiced by James Lovelock in the 1960s. Lovelock has himself appeared less green of late, for example in his conviction that building more nuclear power stations in a must to curb fossil carbon emissions and so to ameliorate global warming. Through "Gaia" the whole earth is viewed as a single large organism with many interdependent systems that cooperate through feedback mechanisms to maintain a viable equilibrium. Human disturbance of this balance of nature is believed to have resulted in a loss of biodiversity and raised the spectra of climate change as an agent of the apocalypse.
Although it would undoubtedly mean a complete revamping of the modern lifestyle, especially in the West, it is thought possible that a population density of 6 to 10 people per acre might be supported through permaculture, and in excess of the number that our current cereal-based food economy can sustain. The word permaculture is a portmanteau that contains elements of permanent agriculture, as well as permanent culture, (and permanent "oil dearth" agriculture) as indeed does its underlying philosophy. The Australians, Bill Mollison and David Holmgren coined the concept in the 1970s via a series of publications, in which they addressed the matter of sustainable (low-input) farming (and living) by means of careful design, to create "living spaces" that are entirely in-flow with their surroundings, including perennial agricultural systems which capture water and the growth of a diversity of species as an overall food source.
This is an entirely reasonable strategy in the sense that much of our labour and energy inputs to sustain modern lifestyles (especially in the industrialised nations) is expended to hold-back nature, and to support a bubble whose longevity is limited by the availability of cheap resources such as oil and natural gas, coal and uranium for nuclear power.Within the natural living space, all materials for living quarters and fuel are provided fully from sustainable, locally sourced materials, i.e. what can be grown within the community.
Two strands of the notion have been identified:
Original Permaculture which aims to create a Forest Garden in which plants and animals (including humans) live in harmony.
Design Permaculture which is a kind of compromise, and uses natural processes to create a sustainable living space ecosystem following ecological principles in a more structured way.
The latter is a significant and necessary adaptation of the "pure" notion, since it is unlikely that some god or God will recreate from scratch a garden of Eden (perhaps the first self-maintaining forest garden, or the idea of it) but it can be used in the less adaptive and more proscriptive integrity of a city.
Original permaculture attempts to closely replicate nature by developing food layers which closely resemble their wilderness equivalents. While the end result of Design permaculture may lack the "natural" appearance of a forest garden, the design rests on similar ecological principles. The strategy chosen is derived from observation and imitation of the natural world. Obviously, this appeals to the "back to nature" movement and its philosophy to reject the industrialised world, which it perceives as the source of all evil. In reality, it is the means for industrialisation that is rejecting us, since our immense use of energy is but a brief fling in the context of human existence. To create a permaculture (forest) garden a layer system is followed where farming is organic and the source of irrigation is rain water. The level of cultivation, including tilling is minimised, according to a minimalist use of energy, including human and animal labour.
Perennials (year round plants) provide leaves, roots (which regenerate the health of the soil) and fruit. The upper storey of tree-cover can provide a staple food e.g. fruit or nuts, while its foliage can be fed to animals or eaten by humans; within the symbiosis of flora and fauna, bees naturally pollinate flowers and provide honey in the process. If there is sufficient living space, pigs and chickens can be kept too, since this is not a necessarily vegan lifestyle. Indeed, in nature, animals and plants have a mutually beneficial relationship. By maintaining a high density of desirable plants, unwanted plants, weeds etc. are out-competed and kept down in volume. By means of a diversity of plant types, pests are reduced further by competition rather than being encouraged as they are in monoculture farming.
As two distinct examples of the success of this approach on the scale of nations, we may note Ethiopia and Cuba. The Ethiopian soil is poor and there is little rain, thus three mutual kinds (levels) of plant growth are employed, all of which provide food. The upper canopy creates a microclimate that tends to retain moisture, and the plant-roots grow at different depths, so they do not compete directly for the water in the same soil space. Cuba is a nation which was forced to adapt when the communist regime collapsed in 1989, and they could no longer rely on gifts of artificial fertilizers, pesticides and fuel for intensive farming as a reward for providing the Russians with a missile and observation base conveniently close to the United States. The fuel-shortages curtailed the transport of crops grown in the rural areas to the cities. Hence a more localised approach has been adopted using permaculture techniques, known as urban farming, in which many small land spaces and even rooftops have been turned into growing areas. Cuba is the more salient example in terms of a necessary adaptation of an industrialised society to a low-input arrangement, as is the challenge now facing the West as it must confront the depletion of reserves of cheap oil and energy per se.
It is no coincidence that modern permaculture found a voice in the 1970s, since this is the time of the first (politically driven) oil crises. It became clear that in order for people to be fed they must flee from industrialised agriculture which without large and constant inputs of cheap liquid fuels and natural gas, will collapse. Without these inputs it could not have risen to its behemoth proportions and its products of monoculture. Permaculture emphasises the exact opposite, on low-input and creating crop-diversity; a protection against putting all one's eggs in one basket... and producing only eggs.
David Holmgren is a major innovator in permaculture design, optimised to achieve the productivity of natural ecosystems, and to use renewable (nature's own) energy sources (wind, gravity, solar power, fires, wave, and so on), to satisfy human needs for food and shelter. Holmgren's zone analysis will be discussed elsewhere. Here is a useful summary of some principles of structure and design.
Layers (The Forest Garden).
In permaculture and forest gardening, seven layers are identified:
(1) The canopy.
(2) Low tree layer (dwarf fruit trees).
(5) Rhizosphere (root crops).
(6) Soil Surface (cover crops).
(7)Vertical layer (climbers, vines).
An eighth layer, Mycosphere (fungi), is often included.
In a mature ecosystem manifold and complex interactions are established over a long time. For example in an ancient woodland there are mutual relationships between e.g. trees, understory, ground cover, soil, fungi insects and other animals and birds. Plants grow at different heights and set their roots to according different depths into the soil. This is biodiversity in action, namely that a diverse and interactive community flourishes in a relatively limited space. Also, plants come into leaf and fruit at different times of year - "Come into season" it was called before everything was available throughout the year by energy-intensive growing methods and global imports. However, I think we have lost yet more of our connection with the flow of nature. We are less aware of the changing seasons of growth throughout the course of the year, and the rich and unique bounty that each one brings.
Holmgren's 12 design principles.
These are restatements of the principles of permaculture from David Holmgren's Permaculture: Principles and Pathways Beyond Sustainability; Also see permacultureprinciples.com:
(1) Observe and interact - By taking the time to engage with nature we can design solutions that suit our particular situation.
(2) Catch and store energy - By developing systems that collect resources when they are abundant, we can use them in times of need.
(3) Obtain a yield - Ensure that you are getting truly useful rewards as part of the work that you are doing.
(4) Apply self-regulation and accept feedback - We need to discourage inappropriate activity to ensure that systems can continue to function well.
(5) Use and value renewable resources and services - Make the best use of nature's abundance to reduce our consumptive behaviour and dependence on non-renewable resources.
(6) Produce no waste - By valuing and making use of all the resources that are available to us, nothing goes to waste.
(7) Design from patterns to details - By stepping back, we can observe patterns in nature and society. These can form the backbone of our designs, with the details filled in as we go.
(8) Integrate rather than segregate - By putting the right things in the right place, relationships develop between those things and they work together to support each other.
(9) Use small and slow solutions - Small and slow systems are easier to maintain than big ones, making better use of local resources and producing more sustainable outcomes.
(10) Use and value diversity - Diversity reduces vulnerability to a variety of threats and takes advantage of the unique nature of the environment in which it resides.
(11) Use edges and value the marginal - The interface between things is where the most interesting events take place. These are often the most valuable, diverse and productive elements in the system.
(12) Creatively use and respond to change - We can have a positive impact on inevitable change by carefully observing, and then intervening at the right time.