Modern industrial agriculture is largely responsible for environmental problems, such as biodiversity loss, soil degradation, and alteration of biogeochemical cycles or greenhouse gas emission. Agroecology, as a scientific discipline as well as an agricultural practice and movement, emerged as a response to these problems, with the goal to create a more sustainable agriculture. Another response was the emergence of permaculture, a design system based on design principles, as well as a framework for the methods of ecosystem mimicry and complex system optimization. Its emphasis, being on a conscious design of agroecosystems, is the major difference to other alternative agricultural approaches. Agroecology has been a scientific discipline for a few decades already, but only recently have design principles for the reorganization of faming systems been formulated, whereas permaculture practitioners have long been using design principles without them ever being scrutinized. Here, we review the scientific literature to evaluate the scientific basis for the design principles proposed by permaculture co-originator, David Holmgren. Scientific evidence for all twelve principles will be presented. Even though permaculture principles describing the structure of favorable agroecosystems were quite similar to the agroecological approach, permaculture in addition provides principles to guide the design, implementation, and maintenance of resilient agroecological systems.

Permaculture is proposed as a tool to design and manage agroecological systems in response to the pressing environmental challenges of soil degradation, climate change and biodiversity loss. However, scientific evidence on the effects of permaculture is still scarce. In this comprehensive study on a wide range of soil and biodiversity indicators, we examined nine farms utilizing permaculture and paired control fields with locally predominant agriculture in Central Europe. We found 27% higher soil carbon stocks on permaculture sites than on control fields, while soil bulk density was 20% lower and earthworm abundance was 201% higher. Moreover, concentrations of various soil macro- and micronutrients were higher on permaculture sites indicating better conditions for crop production. Species richness of vascular plants, earthworms and birds was 457%, 77% and 197% higher on permaculture sites, respectively. Our results suggest permaculture as effective tool for the redesign of farming systems towards environmental sustainability.

Permaculture is a promising framework to design and manage sustainable food production systems based on mimicking ecosystems. However, there is still a lack of scientific evidence especially on the crop productivity of permaculture systems. In this first study on permaculture yield, we collected yield data of eleven permaculture sites in Germany and surrounding countries, that also work according to organic guidelines. We used the Land Equivalent Ratio (LER) as an index to compare mixed cropping systems of permaculture sites with average monoculture yield data of the overall German agricultural sector, as well as that of only organic German agriculture. An LER of 1 indicates equal yields of the compared polyculture and monoculture, while an LER of 1.2 would indicate a 20% higher productivity of the polyculture. Mean permaculture LER as compared to total German agriculture was 0.80 ± 0.27 and 1.44 ± 0.52 as compared to German organic agriculture, both with no significant difference to 1. Our results imply, that yields of permaculture sites are comparable to predominant industrial agriculture. The observed productivity may result from the application of key permaculture principles, such as utilizing diversity and mutually supportive species and improving soil health, which contribute to system stability and resource efficiency. Provided that future studies will support our findings, permaculture could combine soil, biodiversity and climate protection with agricultural productivity. Most importantly, the variables that determine the difference in crop productivity among permaculture sites need to be identified and evaluated.

1 Permaculture is a promising framework to design and manage sustainable food production systems based on mimicking ecosystems. However, there is still a lack of scientific evidence especially on the crop productivity of permaculture systems. In this first study on permaculture yield, we collected yield data of eleven permaculture sites in Germany and surrounding countries, that also work according to organic guidelines. We used the Land Equivalent Ratio (LER) as index to compare mixed cropping systems of permaculture sites with average monoculture yield data of the overall German agricultural sector, as well as that of only organic German agriculture. An LER of 1 indicates equal yields of the compared polyculture and monoculture, while an LER of 1.2 would indicate a 20% higher productivity of the polyculture. Mean permaculture LER as compared to total German agriculture was 0.80 ± 0.27 and 1.44 ± 0.52 as compared to German organic agriculture, both with no significant difference to 1. Our results imply, that yields of permaculture sites are comparable to predominant industrial agriculture. The observed productivity may result from the application of key permaculture principles, such as utilizing diversity and mutually supportive species and improving soil health, which contribute to system stability and resource efficiency. Provided that future studies will support our findings, permaculture could combine soil, biodiversity and climate protection with agricultural productivity. Most importantly, the variables that determine the difference in crop productivity among permaculture sites need to be identified and evaluated.