The seventh Permaculture Design principle is ‘Small Scale Intensive Systems’.
In Permaculture, we design and build small scale systems because they can be managed with less resources, which makes them very energy efficient.
We also construct these systems as intensive systems to obtain the maximum productivity from these smaller manageable spaces.
Where possible, these systems are scaled so they can be managed with human labour and simple hand tools. Such systems use very little energy and can provide a very high energy return on the energy invested . Typically, in systems utilising human labour, such as peasant farming, one person can produce enough food to support 8-10 people, so the ratio of energy we produce to the energy we use is as high as 10:1. In these small scale systems, we don’t just use human labour though, we can also use animals too, and where absolutely necessary we can use light machinery that uses moderate amounts of fuel, such as a small tractor.
Obviously, acre for acre, a small farm utilising human labour, animals, and possibly light machinery is going to be far more energy efficient than hundreds of acres of commercial farmland employing heavy machinery, which then transports the food over vast distances and stores it in cold storage.
The Permaculture small scale intensive systems described so far might sound fairly similar to peasant farming systems or small scale agriculture at this point, but this is where the similarity ends. Let us look at some of these difference in detail that distinguish Permaculture systems from the other systems, and the benefits these differences provide.
Perennial Plants Instead of Annual Plants
Annual plants are very short-lived plants that only live for a year, produce seed and then die down. Perennial plants are plants that don’t die down after a year, they can live for many years to many centuries, as in the case of trees.
In Permaculture systems, we do not rely exclusively or extensively on annual crops for food production as conventional agricultural systems do – the preference is to use perennial plants for food production wherever possible.
Nature predominately consists of perennial plants. When you look at natural terrestrial (land based) and freshwater aquatic ecosystems, the majority of plants are in fact perennial. There are very good reasons for this. Perennial plants form stable, resilient, biodiverse ecosystems.
In Permaculture, we model our designs and systems on those of Nature, and by replicating these perennial ecosystems, we can create stable, resilient food production systems.
Annual vs. Perennial Plants
If we look at the biology of annual and perennial plants, we can further understand the advantages of perennials, and their predominance in Nature.
Annual plants have a “live fast, die young” strategy – their survival/reproduction strategy is to reproduce from seed, grow very fast, using a very large amount of soil nutrients in the process to grow to as fast as possible, and to eventually produce large quantities of seed within the same year, before they finally die down. This very fast growth pattern does not give the plant much time to establish itself, it is an all out effort to get to the seeding stage before the growing season ends.
Typically, annual plants are very shallow rooted, for most vegetables, the bulk of the root mass is within the top 6” (15cm) of the soil, so they cannot access water and nutrients deeper in the soil, and their root networks are not capable of stabilising the soil to prevent soil erosion. Annuals do not form permanent ecosystems because once they reach the end of their growing season and they have gone to seed, they die down leaving bare soil once again.
If you look at either a backyard vegetable garden or a commercial farm covering hundreds of acres of land, it works exactly the same way. Seeds or seedlings are planted, they grow very fast after being given huge amounts of fertiliser, they are harvested, the soil becomes bare again, then next year they are replanted once again, and the cycle runs indefinitely. To prevent localised nutrient deficiencies and disease, the practice of crop rotation is used, where different plants are planted in each bed every season, and moved from one bed to the next each successive year.
Perennial plants have a very different survival/reproduction strategy. They can grow from seed or from offshoots of existing plants, and they grow quite slowly in comparison to annuals, taking their time to establish themselves. They grow extensive root systems that tap very deep into the soil, allowing them to access water and nutrients that cannot be reached by annual plants, providing a permanent network of roots in the soil that help stabilise the soil and prevent erosion.
Because they grow slowly, perennials do not need large quantities of nutrients all at once like annuals do to grow. In fact, perennials are much better adapted than annuals to grow in low nutrient environments, and can obtain their nutrients progressively from the soil over a longer period of time. In warmer climates perennials can grow continually, and in colder climates where they stop growing when the climate is unfavourable, they are able to resume growth earlier than annuals.
Perennials, being long lived, create stable ecosystems such as forests, which can provide a food source and a home for a diverse range of flora and fauna. Forests are home to approximately 50-90% of all the world’s terrestrial (land-living) biodiversity. Tropical forests alone are estimated to contain between 10-50 million species – over 50% of species on the planet. Annual farmlands are only a temporary home to pest insects, nothing else.
Perennial plants don’t need to be replanted every year, so the arduous seasonal task of ploughing, digging and sowing seed that is carried out for annual crops is no longer a concern.
Less fertiliser and water is required to grow perennial plants, and they are on the whole a lot more productive than annuals. Growing perennial food plants is a far more sustainable and energy efficient, and requires far less work.
Use of Biological Resources
This area is covered in depth in the fifth Permaculture Design principle ‘Using Biological Resources’.
This strategy is concerned with the use of biological resources to do work or conserve energy, rather than using non-renewable energy sources such as fossil fuel resources. Wherever we can use a plant or animal to preform a certain function in our designs, then this is our preferred approach.
For example, in a small scale intensive system, we can use mulching as a preventative measure for weed control rather than using herbicides after the weeds have grown. We can also use ground covers as living mulches to shade out and out-compete any weed seeds that might find their way into the soil.
Another example is fertilising – rather than use synthetic chemical fertilisers, we can use a range of sustainable and energy-efficient options, such as nitrogen-fixing plants, animal manures, dynamic accumulator plants and green manures.
Biological resources are a key to recycling energy and materials, so by using biological resources we can work with Nature to gain many benefits in terms of energy efficiency over systems that only harness human labour or are unsustainably powered by non-renewable fossil fuels.
Use of Alternative Technology to Generate or Save Energy
In Permaculture, small scale intensive systems can utilise alternative technologies to generate or save energy. These measures contribute to the high energy efficiency of permaculture designs by making best use of the energy available and harnessing it for use on site.
- Energy can be generated using renewable sources such as solar power, hydro systems, wind power, wood and other sources of biomass.
- Energy can be saved through energy cycling – see the sixth Permaculture Design principle ‘Energy Cycling’. In our Permaculture designs, we seek to capture energy to increase the growth of our living systems, and set in place cycles which will perpetuate life. The strategy here is to take energies flowing through a site and to divert them into ‘cycles’ to allow them to be utilised to ultimately increase the available energy on the site.
Plant Stacking – stacking in vertical space
In a forest, Nature grows plants in a highly optimised pattern, utilising multiple layers and making the most of both horizontal and vertical space. A forest typically is comprised of seven layers, and in Permaculture we design food forests in the same way, as shown below:
In this system, plants grow in forests in a “stacked” layout, as detailed below:
- Tall trees form the uppermost canopy layer– typically large fruit and nut trees.
- Smaller trees form the next layer– typically lower growing and dwarf fruit trees.
- Shrubs sit beneath the small trees – these are well represented by currants and berries.
- Herbaceous plants occupy the next layer – these are the culinary and medicinal herbs, companion plants, bee-forage plants and poultry forage plants.
- Ground cover plants carpet any remaining space on the ground, forming a living mulch that protects the soil, reduces water loss to evaporation, and prevents weeds growing.
- Rhizosphere or root zone plants go a level deeper into the underground level – these are the root crops, such as potatoes, onions, carrots, ginger and yacon.
- Climbers and vines rise upwards to occupy vertical space. They can be run up trellises, arbours, fences, trees or any other vertical support. This category includes grapes, climbing beans, many berries, passionfruit, kiwi fruit, climbing peas, chokos and many other species that love to climb.
The benefits of a stacked forest design are as follows:
- Very high yields are possible because of the vertical stacking of up to seven layers of trees and plants in the one space to create an intensive planting system.
- A microclimate is created by the close arrangement of plants, which allows plants to grow in a protected space where they are not subjected to harsh conditions.
- Companion planting – the intensive mixed planting of various species creates a biodiverse environment which allows synergy between plants, where plants help each other grow, protect each other from pests and diseases, and increase productivity.
Succession Planting – stacking in time
In Nature new plants are already growing well before the old ones have died down, so soil is never left bare.
If we plant different crops with each other that have different growing seasons, we can plan it so that as the existing plants are coming to the end of their fruiting/productive cycle for the season, new plants are beginning to grow – we can “stack plants in time” to get extended cropping throughout the season, without having bare spaces in the garden or ‘slack time’ when nothing is growing.
For example, we can plant our cold season crops such as broad beans while our warm season crops, such as tomatoes are approaching the latter part of their life. By the time the tomatoes begin to decline, the broad beans will be growing strongly to fill place in the garden beds.
This table summarises the differences discussed so far between conventional farming systems, peasant farming systems and Permaculture systems.
| Conventional Farming Systems | Peasant Farming Systems | Permaculture Systems | |
| crop type | mainly annual crops | mainly annual crops | mainly perennial crops |
| soil cultivation | energy (fossil fuel) intensive soil cultivation | human labour intensive soil cultivation | use of biological resources |
| human labour use | low – fossil fuel powered & machinery driven | total dependency on human labour | limited use of human labour |
| machinery use | heavy use of machinery | little or no use of machinery | only if needed, moderate use of machinery |
| energy saving or energy generation | none | energy efficiency through use of human labour & animals | use of biological resources and alternative technologies |
The design principle Small Scale Intensive Systems is about using small manageable areas of land as efficiently and sustainably as possible, using biological resources and designs that imitate Nature, to reduce human labour and to leverage natural ecological processes to our benefit, so we can obtain maximum yields with the least effort in the most ecologically sound way possible.
In Permaculture, since we care for the planet, and work with Nature, it is important that the site we design and construct is not too big for us to manage. We must be able to keep what we construct under control. If we lose control of the site, and it gets overrun with weeds, then what we have in fact done is damage a natural system, which Nature will have to repair.
An important principle in Permaculture design, to quote Bill Mollison’s “Introduction to {Permaculture”, is “…if we cannot maintain or improve a system, we should leave it alone, thus minimising damage and preserving natural complexity.”
It is too easy to ‘bite off more than we can chew’, and build a very large, extensive site, which is too big too look after. Inevitably, if we cannot maintain all the plants and trees on a site, they will die, which is a huge waste of life and resources, and the natural systems which occupied the area previously will have also been lost in the process. The net result being wholesale destruction of Nature, something we would prefer to avoid!
When designing a small scale intensive permaculture system, we always begin designing around the site of the home, and extend out from there. We can progressively extend the design as necessary, but what is critical is that we start small, and we maintain control of the space we have modified, this is the essence of responsible design strategy.