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© 2015 Macmillan Publishers Limited. All rights reserved
Progressing organics
To be sustainable, any farm must meet four goals: productivity, environ-
mental soundness, financial viability and social responsibility. Organic agri-
culture balances multiple sustainability benefits but can it contribute more
to safely feeding the world?
See Nature Plants 1, 15221 (2016).
Image: J. Richardson
Design: S. Witham
c
2015 Macmillan Publishers Limited. All rights reserved.
NATURE PLANTS | VOL 2 | FEBRUARY 2016 | www.nature.com/natureplants 1
Organic agriculture has a history of being contentious.
Emblematic of this, and representing the prevailing attitudes
of many farmers and scientists in the 1970s and 1980s, are
the unsympathetic words uttered in 1971by then US Secretary of
Agriculture Earl Butz: “Before we go back to organic agriculture in
this country, somebody must decide which 50 million Americans
we are going to let starve or go hungry”1. At the turn of the twenty-
rst century, sceptics considered organic agriculture to be ideologi-
cally driven and inecient2,3. ey argued that organic agriculture
relies on more land to produce the same amount of food as con-
ventional agriculture and that adopting organic agriculture on too
large a scale could potentially threaten the world’s forests, wetlands
and grasslands2,3. ey also asserted that organic agriculture has too
many shortcomings and poor solutions to agricultural problems2,4.
Organic agriculture is still considered by some critics as being an
inecient approach to food security5,6 and a farming system that
will become less relevant in the future6.
Yet the number of organic farms, the extent of organically farmed
land, the amount of research funding devoted to organic farming and
the market size for organic foods have steadily increased7. Sales of
organic foods and beverages are rapidly growing, increasing almost
vefold between 1999and 2013to US$72 billion (ref.7; Fig.1); this
2013 gure is projected to double by 2018. Moreover, recent interna-
tional reports recognize organic agriculture as an innovative farm-
ing system that balances multiple sustainability goals and will be of
increasing importance in global food and ecosystem security8–10.
Here, we review the performance of organic farming systems
in the context of sustainability metrics and global challenges, and
examine some of the barriers to the adoption of organic farming
systems and the policies needed to overcome them.
Organic practices and certification
Organic agriculture, sometimes called biological or ecological
agriculture, combines traditional conservation-minded farming
methods with modern farming technologies. It emphasizes rotating
crops, managing pests naturally, diversifying crops and livestock,
and improving the soil with compost additions and animal and
green manures (Fig.2). Organic farmers use modern equipment,
improved crop varieties, soil and water conservation practices, and
Organic agriculture in the twenty-first century
John P. Reganold* and Jonathan M. Wachter
Organic agriculture has a history of being contentious and is considered by some as an inecient approach to food production.
Yet organic foods and beverages are a rapidly growing market segment in the global food industry. Here, we examine the per-
formance of organic farming in light of four key sustainability metrics: productivity, environmental impact, economic viability
and social wellbeing. Organic farming systems produce lower yields compared with conventional agriculture. However, they are
more profitable and environmentally friendly, and deliver equally or more nutritious foods that contain less (or no) pesticide
residues, compared with conventional farming. Moreover, initial evidence indicates that organic agricultural systems deliver
greater ecosystem services and social benefits. Although organic agriculture has an untapped role to play when it comes to the
establishment of sustainable farming systems, no single approach will safely feed the planet. Rather, a blend of organic and
other innovative farming systems is needed. Significant barriers exist to adopting these systems, however, and a diversity of
policy instruments will be required to facilitate their development and implementation.
the latest innovations in feeding and handling livestock. Organic
farming systems range from strict closed-cycle systems that go
beyond organic certication guidelines by limiting external inputs
as much as possible to more standard systems that simply follow
organic certication guidelines.
Rudolf Steiner’s 1924 course on biodynamic agriculture sparked
the evolution of organic agriculture in Europe1. Organic agricul-
ture was established in its own right in the 1930s and 1940s, being
developed in Britain by Lady Eve Balfour and Sir Albert Howard,
in Switzerland by Hans Mueller, in the United States by J. I. Rodale
and in Japan by Masanobu Fukuoka1. By the 1970s, organic foods
had grown in popularity, prompting the rst organic certication
standards to be draed in Europe and the United States, and com-
mencing an ongoing evolution of certiers that now includes 283
organic certication bodies worldwide operating in 170 countries7.
is proliferation of certiers reects both a complex history of
sometimes competing independent standards and the demand for
access to certiers around the world.
Many farms in both developed and less-developed countries
implement organic practices but are not certied organic. However,
growers are increasingly turning to certied organic farming sys-
tems as a way to provide verication of production methods,
decrease reliance on non-renewable resources, capture high-value
markets and premium prices, and boost farm income. Although
requirements vary slightly between certifying agencies, they pro-
mote soil quality, crop rotations, animal and plant diversity, bio-
logical processes, and animal welfare, while generally prohibiting
irradiation, sewage sludge, genetic engineering, the prophylactic
use of antibiotics, and virtually all synthetic pesticides and fertiliz-
ers. Standards continue to evolve with changing technologies and
socioecological conditions; some requirements are based on scien-
tic evidence, whereas others are driven by ideology.
As most certication standards originated in temperate devel-
oped countries, they are not always applicable in other regions, espe-
cially in less-developed countries. High demand for organic foods
in Europe and North America has resulted in the import of organic
foods from large farms in less-developed countries7. Although pre-
mium prices for exported foods may be benecial to farmers, the
inaccessibility of many of these foods to local consumers raises
Department of Crop and Soil Sciences, Washington State University, Pullman, Washington 99164, USA.
*e-mail: reganold@wsu.edu
REVIEW ARTICLE
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© 2016 Macmillan Publishers Limited. All rights reserved
2 NATURE PLANTS | VOL 2 | FEBRUARY 2016 | www.nature.com/natureplants
questions about food security and social equity. Participatory guar-
antee systems, which rely on local stakeholder verication, have
emerged as a more locally focused alternative to traditional certi-
cation7, and could lead to the development of more locally relevant
visions for the production and consumption of organic foods.
Sustainability of organic agriculture
About 38% of Earth’s land cover is occupied by agriculture11.
Although agriculture provides growing supplies of food and other
products, it is a major contributor to greenhouse gases, biodiversity
loss, agrochemical pollution and soil degradation12–14. Most of these
environmental consequences come from arable land, which com-
prises around 12% of the land cover11. e challenge of feeding a
growing population expected to reach 9to 10 billion people by 2050
while protecting the environment is daunting. Adopting truly sus-
tainable farming systems on a wide scale is our best opportunity for
meeting this grand challenge and ensuring future food and ecosys-
tem security. Concerns about the unsustainability of conventional
agriculture have promoted interest in other farming systems, such
as organic, integrated and conservation agriculture8–10.
According to a US National Academy of Sciences report10, any
farm, be it organic or conventional, can only be deemed sustain-
able if it produces adequate amounts of high-quality food, enhances
the natural-resource base and environment, is nancially viable,
and contributes to the wellbeing of farmers and their communi-
ties. With the rise of organic farming in the past two decades, hun-
dreds of research studies comparing dierent aspects of organic and
conventional farming systems have been published. is section
focuses on assessing such comparison studies across these four sus-
tainability areas.
Production. Production includes crop and animal yield and their
quality. Numerous individual studies have compared yield dier-
ences between organic and conventional systems. ese data have
been synthesized in several meta-analyses or reviews; accord-
ing to these studies, yield averages are 8to 25% lower in organic
systems15–19. However, with certain crops, growing conditions and
management practices, organic systems come closer to matching
conventional systems in terms of yields. According to one such
synthesis study, the best yielding organically grown crops or crop
groups are rice, soybeans, corn and grass-clover, which yield 6 to
11% less than conventional systems; the lowest yielding are fruits
and wheat, which yield 28and 27% less, respectively17. Another
meta-analysis found fruits, soybeans and oil seed to be the highest
yielding organic crops, and wheat and vegetables the lowest, yield-
ing 37and 33% less than conventional systems respectively18. In
cases where organic crop rotations depend on green manure crops,
food production over the whole rotation may be lower than one-to-
one crop yield comparisons suggest17.
Although meta-analysis is a great tool that can describe broad
patterns not immediately visible in primary eld research19,20, it
must also be treated with caution, because no single farming sys-
tem or practice works best everywhere. Still, these studies15–19 give
strength to the argument that adoption of organic agriculture
under agroecological conditions where it performs best may close
the yield gap between organic and conventional systems. Under
severe drought conditions, which are expected to increase with
climate change in many areas, organically managed farms have
frequently been shown to produce higher yields than their conven-
tional counterparts21,22, due to the higher water-holding capacity of
organically farmed soils23. In addition, improvements in manage-
ment techniques and crop varieties for organic systems may also
close this yield gap. For example, direct selection of wheat cultivars
in organic systems has resulted in improved yields in organic sys-
tems when compared with indirect selection of wheat cultivars in
conventional systems24.
Whereas organic systems yield less food, organic foods have
signicantly less to no synthetic pesticide residues compared with
conventionally produced foods25–28. Studies have also found that
children who eat conventionally produced foods have signicantly
higher levels of organophosphate pesticide metabolites in their
urine than children who eat organically produced foods29,30. In 2012,
the American Academy of Pediatrics reported that an organic diet
reduces children’s exposure to pesticides, and provided resources
for parents seeking guidance on which foods tend to have the high-
est pesticide residues31. Although these data show that organic foods
Sales of organic food (US$billion)
Organic land area (ha × 10
6
)
Sales, Europe
Sales, other
Sales, North America
Global sales, no breakdown
Organic land area
80
70
60
50
40
30
20
10
0
45
40
35
30
25
20
15
10
5
0
1997
1998
2000
1999
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
Year
Figure 1 | Annual global market for organic foods and land area of organic
production. Increasing sales of organic food in nominal billions of US
dollars (bars), broken down by contributions from North America (red),
Europe (green) and the rest of the world (orange), and increasing total
global land area under organic production in millions of hectares (blue
line)7,96–98. European and North American contributions were not available
for the years 1998 through 2000, shown in grey.
Biologically
active soil
Diverse
crop and
livestock
rotation
Balanced
nutrient
supply
Disease
management
Physical methods
Species, variety
and breed
selection
Supplementary
lime, organic
fertilizers and
compost
Hedges,
margins
and other
habitat areas
Biological
controls
Food, fibre and fuel for
human and livestock use
and consumption
Crop and
animal
health Weed
management
Biological
controls
Pest
management
Temporal and
spatial patterns
Diverse
species
balance
Figure 2 | Organic management practices. The complex interactions
among structural factors and tactical management strategies on a
diversified organic farm producing food, fibre and fuel for human and
livestock use and consumption. Structural factors, represented by
circles, are the foundation of organic management, with diverse crop and
livestock rotations at the centre. Tactical management decisions are used
to supplement the structural factors and include the use of: biological
controls; supplementary lime, organic fertilizers and compost; hedges,
margins and other habitat areas; species, variety and breed selection;
temporal and spatial patterns; and physical weed management. Figure
adapted from ref.99, © 2001 Elsevier.
REVIEW ARTICLE NATURE PLANTS DOI: 10.1038/NPLANTS.2015.221
© 2016 Macmillan Publishers Limited. All rights reserved
NATURE PLANTS | VOL 2 | FEBRUARY 2016 | www.nature.com/natureplants 3
may present some clear advantages when it comes to synthetic pes-
ticide residues, the human health impacts of pesticide exposure
from food are not clear26, and organically certied pesticides need
to be better identied and taken into account28.
At least 15 reviews or meta-analyses26,27,32–44 of the scientic
literature comparing the nutrition of organic and conventional
foods have been published in the past 15years. Twelve of these
studies27,32–34,36–39,41–44 found some evidence of organic food being
more nutritious (for instance, having higher concentrations of
vitaminC, total antioxidants and total omega-3 fatty acids, and
higher omega-3to -6 ratios). Whether or not these are nutritionally
meaningful dierences continues to be debated26,43. e other three
studies26,35,40 concluded that there were no consistent nutritional dif-
ferences between organic and conventional foods. However, one of
the three studies found that conventional chicken and pork had a
33% higher risk for contamination with antibiotic-resistant bacteria
compared with organic alternatives26.
Environment. Reviews and meta-analyses generally support the
perception that organic farming systems are more environmentally
friendly than conventional farming systems45–58. For example, such
aggregate studies have found that organic farming systems con-
sistently have greater soil carbon levels, better soil quality and less
soil erosion compared with conventional systems45–51. In addition,
organic farms generally have more plant diversity, greater faunal
diversity (insects, soil fauna and microbes, birds) and oen more
habitat and landscape diversity46–55. Most functional groups, such as
herbivores, pollinators, predators and producers (plants), are more
diverse in organic farming systems51–53. Moreover, in a study cov-
ering eight western and eastern European countries, insecticides
and fungicides had consistently negative eects on biodiversity,
with insecticides also reducing the biological control potential in
farming systems56.
As organic agriculture uses virtually no synthetic pesticides,
there is little to no risk of synthetic pesticide pollution of ground
and surface waters46. With respect to nitrate and phosphorous leach-
ing and greenhouse gas emissions, organic farming systems score
better than conventional farming when expressed per unit produc-
tion area46,49,51,57,58; however, given the lower land-use eciency of
organic farming in developed countries, this positive eect is less
pronounced and in some cases reversed when expressed per unit
product49,57,58. In a meta-analysis of environmental quality param-
eters, organic farms were found to have lower nitrate leaching,
nitrous oxide emissions and ammonia emissions per unit of eld
area, but higher leaching and emissions per unit product48. Severe
degradation of freshwater and marine ecosystems around the world
is linked to excessive use of nitrogen and phosphorous fertiliz-
ers12,59, leading to eutrophication of freshwater and the production
of hypoxic zones in coastal waters. Lower nutrient pollution from
organic compared with conventional systems can be illustrated by
dierences in their nitrogen cycling and losses (Fig.3).
Organic systems are usually more energy ecient than their
conventional counterparts46–48,51,54,58. For example, in Germany, Italy,
Sweden and Switzerland, organic farms were found to use signi-
cantly less energy on a per-hectare basis than their conventional
counterparts, and 70% of organic farms and 30% of conventional
farms had signicantly lower energy consumption per unit of out-
put45. e generally lower energy use46–48,54 and higher soil organic
matter45–49 of organic systems make them ideal blueprints for devel-
oping methods to limit fossil fuel emissions and build soil carbon
stores, important tools in addressing climate change.
Economics. Whether organic agriculture can continue to expand
globally will primarily be determined by its nancial performance
compared with conventional agriculture17,60. e main factors that
determine the protability of organic agriculture include crop yields,
labour and total costs, price premiums for organic products, the
potential for reduced income during the organic transition period
(usually three years), and potential cost savings from the reduced
reliance on non-renewable resources and purchased inputs61.
To the best of our knowledge, only one meta-analysis has ana-
lysed the nancial performance of organic and conventional agri-
culture20. e analysis combines ndings from 40years of studies
covering 55 crops grown on ve continents. When actual price
premiums (higher prices awarded to organic foods) were included,
organic agriculture proved signicantly more protable (22to 35%
greater net present values) and had higher benet/cost ratios (20to
24%) than conventional agriculture. When organic premiums
were taken away, net present values (−27to −23%) — net returns
accounting for the time value of money — and benet/cost ratios
(−8to −7%) of organic agriculture were signicantly lower than
conventional agriculture20.
Mineralization
N export
in harvest
N export
in harvest
Crop N
uptake
Erosion N loss
Immobilization
Atmospheric
N deposition
Atmospheric
N deposition
Volatile N loss
during senescence
Volatile N loss
during senescence
N leaching
Crop residue N return
N loss through
denitrification
N loss through
denitrification
Fertilizer N
addition
Fertilizer N
addition
Biological
N fixation
Biological
N fixation
a
Mineralization
Crop N
uptake
Erosion N loss
Immobilization
N leaching
Crop residue N return
N runoN runo
b
N added in
manure and
amendments
N added in
manure and
amendments
Gaseous
N loss
Gaseous
N loss
N fixed
by lightning
N fixed
by lightning
Soil
organic N Crop N
Soil
mineral N Crop N
Soil
organic N
Soil
mineral N
Figure 3 | Hypothetical nitrogen stocks and flows of two contrasting cropping systems. a,b, Cropping systems relying mainly on mineral nitrogen inputs
(a) have relatively higher nitrogen losses to air and water than cropping systems with emphasis on biological N fixation, manure and other organic matter
amendments, cover crops and perennial crops, and low reliance on mineral N fertilizer, such as organic and integrated systems (b). The width of the
arrows is relative to the size of the nitrogen flux; boxes representing nitrogen stocks are not scaled to the pool size. Figure adapted from ref.100, © 2015
The National Academies100. Arrows represent nitrogen inputs (green), losses (orange) and transformations (blue).
REVIEW ARTICLE
NATURE PLANTS DOI: 10.1038/NPLANTS.2015.221
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Although price premiums were 29to 32%, breakeven premi-
ums necessary for organic prots to match conventional prots
were only 5to 7%, even with organic yields being 10to 18% lower.
e size of organic premiums awarded, and the dierence between
organic premiums and breakeven premiums, were consistent dur-
ing the 40-year study period. e fact that organic premiums were
signicantly higher than breakeven premiums suggests that organic
agriculture can continue to expand even if premiums decline. e
study also found that total costs were not signicantly dierent, but
labour costs were signicantly (7to 13%) higher with organic farm-
ing practices20. Although one of the successes of conventional agri-
culture has been its ability to produce more with less labour, some
have found the extra labour of organic agriculture to be benecial
in providing rural employment and development opportunities62,63.
Few economic studies have accounted for negative externalities
(such as environmental costs) or positive externalities (such as eco-
system services), with associated monetary values, in organic and
conventional comparison studies. Putting a price on the negative
externalities caused by farming, such as soil erosion or nitrate leach-
ing into groundwater, would make organic agriculture even more
protable, given that its environmental impact is less than that of
conventional agriculture45–58. Indeed, it has been estimated that a
switch to organic production would lower the external costs of agri-
cultural production in the United Kingdom by 75%, from £1,514
million yr–1 to £385 million yr–1 (ref.64).
A number of studies (for example, refs65,66) have compared
ecosystem services in organic and conventional farming systems.
A few of these studies have accounted for the monetary value of
ecosystem services; these studies generally show that conventional
practices decrease the ability of farms to provide some economically
signicant ecosystem services relative to organic practices67–69. For
example, in a study comparing 14 organic arable elds with 15 con-
ventional ones in New Zealand70, the total economic value of three
ecosystem services (biological pest control, soil formation and the
mineralization of plant nutrients) in the organic elds was signi-
cantly greater at US$232ha−1yr−1 compared with the conventional
elds at US$146ha−1yr−1. Factoring in such dierences in economic
comparison studies would probably make up for price premiums
awarded to organic products. Price premiums and European sub-
sidies for organic farms are oen justied on the grounds that they
compensate farmers for providing ecosystem services or avoiding
damage to the environment.
Wellbeing. How well organic, conventional and other farming
systems are performing in areas such as social equity (for instance,
issues of gender, race, ethnicity and class) and quality of life for farm
families and communities remains unclear due to limited research.
Available data indicate that both organic and conventional farming
systems need to make signicant progress to meet social sustain-
ability goals10. However, organic farming has been shown to have
some sociocultural strengths, such as positive shis in community
economic development, increased social interactions between farm-
ers and consumers71,72, and greater employment of farm workers and
cooperation among farmers62,63.
Although organic farming oen requires additional manual
work on the farm, it reduces the exposure of farm workers to pesti-
cides and other chemicals. Such exposure can be particularly prob-
lematic in less-developed countries, where illnesses and death have
resulted from occupational and accidental exposure (due in part
to the fact that it is impractical and expensive for workers to use
safety equipment)73,74.
Organic certication programmes have adopted social wellbe-
ing goals. Guidelines of the International Federation of Organic
Agriculture Movements (IFOAM) stipulate that organic farmers
should be able to support themselves and other workers with fair
incomes, while maintaining safe and dignied working conditions75.
Furthermore, organically certied animals must be raised humanely
under conditions that allow for the expression of their natural behav-
iours and needs75. For example, European Union, US and Japanese
rules on organic production require livestock to have access to open
air or grazing whenever possible, and that sick animals be treated as
needed, even with the use of antibiotics if required76–78.
Organic farming can improve food security by diversifying
on-farm crop and livestock operations, which diversies income
sources and improves variety in diets79. Organic farming necessi-
tates diverse crop and livestock rotations, encourages the integration
Conventional
Biodiversity
Profitability
Total costs
Ecosystem
services
Employment
of workers
Minimize
pesticide
residues
Nutritional
quality
Yield
Minimize
energy
use
Minimize
water
pollution
Organic
Reduce
worker
exposure to
pesticides
Soil quality
Biodiversity
Profitability
Total costs
Ecosystem
services
Employment
of workers
Minimize
pesticide
residues
Nutritional
quality
Yield
Minimize
energy
use
Minimize
water
pollution
Reduce
worker
exposure to
pesticides
Soil quality
Figure 4 | Assessment of organic farming relative to conventional farming in the four major areas of sustainability. Lengths of the 12 flower petals
are qualitatively based on the studies discussed in this Review15–23,25–29,32–56,58,62–74 and indicate the level of performance of specific sustainability metrics
relative to the four circles representing 25, 50, 75 and 100%. Orange petals represent areas of production; blue petals represent areas of environmental
sustainability; red petals represent areas of economic sustainability; green petals represent areas of wellbeing. The lengths of the petals illustrate that
organic farming systems better balance the four areas of sustainability.
REVIEW ARTICLE NATURE PLANTS DOI: 10.1038/NPLANTS.2015.221
© 2016 Macmillan Publishers Limited. All rights reserved
NATURE PLANTS | VOL 2 | FEBRUARY 2016 | www.nature.com/natureplants 5
of multiple farm enterprises and encourages the use of leguminous
crops for biological nitrogen xation. By growing a higher diversity
of more nutrient-rich (such as vegetables) and more protein-rich
(such as legumes and meats) foods, whether for export or subsist-
ence, a farmer has access to at least a portion of these foods. For
example, following 840 small organic and non-organic farms in the
Philippines, researchers found the increase in vegetable and protein
consumption from 2000to 2007to be two to three times greater for
the more diversied organic farmers than conventional farmers80.
Balancing sustainability metrics. Some argue that signicantly
scaling-up organic land area may increase nitrogen and other nutri-
ent limitations on yields17, and question whether the greater land
area required by organic agriculture to maintain yields counteracts
its environmental gains2,3. Probably the biggest criticism of organic
agriculture is its lower yields compared with conventional agricul-
ture4,5, a particularly salient challenge given the task of feeding a
growing world population without further agricultural expansion13.
Conversely, some contend that the environmental advantages of
organic agriculture far outweigh the lower yields, and that increasing
research and breeding resources for organic systems would reduce
the yield gap16,17,24,81. Others suggest that multifunctional farming
systems, such as organic, coupled with more plant-based diets and
reduced food waste, are necessary elements of a more sustainable
food system16,54,65. Sometimes excluded from these arguments is the
fact that we already produce adequate kilocalories of food to more
than feed the world but do not provide adequate access to all indi-
viduals82. Globally, 1.9 billion adults are overweight and of these 600
million are obese83, while 793 million people are undernourished
and more than 28% of children under the age of veare stunted due
to malnourishment82,84.
Debates aside, although yield is an important sustainability
metric, the issue is more complicated than kilograms of food per
hectare. Mainstream conventional farming systems have provided
growing supplies of food and other products but oen at the expense
of the other three sustainability goals. Environmental degradation,
public health problems, loss of crop variety and genetic biodiversity,
and severe impacts on ecosystem services have not only accompa-
nied conventional farming systems but have oen extended well
beyond their eld boundaries. Such negative externalities are not
accounted for.
e performance of organic farming systems in the context of
sustainability metrics indicates that they better balance multiple
sustainability goals than their conventional counterparts (Fig.4).
Based on present evidence, we argue that although organic farm-
ing systems produce lower yields compared with conventional agri-
culture, they are more protable and environmentally friendly, and
deliver equal or more nutritious foods with less to no pesticide resi-
dues. In addition, initial evidence indicates that organic agriculture
is better at enhancing the delivery of ecosystem services, other than
yield, as well as some social sustainability benets. Importantly, the
body of research studies has been heavily biased towards developed
countries, whereas studies in the less-developed world, especially in
tropical and subtropical climates, need to be greatly increased.
With only 1% of global agricultural land in organic production7,
and with its multiple sustainability benets, organic agriculture can
contribute a larger share in feeding the world. Yet, signicant barri-
ers to farmers adopting organic practices remain in both developed
and less-developed countries.
Barriers and policies
Obstacles to farmers adopting organic agriculture include power-
ful vested interests and existing policies, a lack of information and
knowledge, weak infrastructure and other economic challenges,
and misperceptions and cultural biases (Fig.5). Global and national
agribusiness corporations, agrochemical industries, commodity
groups and food companies have a strong vested interest in the
conventional agroindustrial model, command ever-greater market
power in the food system and have heavily inuenced public policy
to favour this model10,85. e consolidation of industries, the con-
centration of market power, and many past and current agricultural
policies have led to decreased agricultural diversity10 and have dis-
incentivized agricultural innovation81.
Considerably less public and private funding has been put
towards research and development for organic systems than towards
conventional systems worldwide; this has resulted in a lack of crop
and livestock breeding for organic farming conditions and a dearth
of knowledge and information resources supporting organic farm-
ers17,19. Historically, public funding for research on organic systems
has been higher in Europe than in the United States7. Moreover,
research on organic agriculture in less-developed countries rep-
resents only a small fraction of the overall scientic literature on
the topic17,19,52.
Some farmers face infrastructure and economic barriers, which
include certication costs and access to markets, loans and insur-
ance. Many areas, especially rural regions and less-developed coun-
tries, lack access to additional labour, markets for organic foods,
infrastructure for storage and distribution, or appropriate certi-
cation requirements86,87. Finally, strong cultural biases against the
connotations of organic agriculture, and conventional mindsets
held by some individuals and organizations, limit the spread of
organic practices86,87.
With these obstacles in mind, governments should focus on
creating an enabling environment for the development and adop-
tion of not just organic but also other innovative and more sustain-
able farming systems88. ese eorts must be targeted at improving
agricultural performance in all four areas of sustainability and
will require a diversity of knowledge-based, legal and nancial
policy instruments89.
Knowledge-based policy instruments are needed to create an
enabling environment for agricultural innovation, education and
outreach. Specically, policy instruments must: ensure farmer
and scientist engagement in research and development decision-
making; improve farmer knowledge and capacity through eective
extension and outreach infrastructure, such as the use of farmer
eld schools and communication technologies; and enhance wom-
en’s educational and leadership opportunities90.
Legal instruments must play a stronger role in ensuring open and
competitive markets, limiting commercial inuence in government
and increasing transparency in the food production system. In addi-
tion, they are needed to reduce food waste, to improve the security
of land tenure for farmers, and to develop national targets for trade
policies that promote food and ecosystem security.
Financial instruments are needed to give monetary value to the
externalities that arise from agricultural practices and to empower
farmers through access to capital, infrastructure and competitive
markets88. In developed countries, direct and indirect crop subsidies
and biofuel incentives should be replaced by targeted agro-environ-
mental incentives, such as payments for biodiversity protection
and soil conservation. Some policy organizations have found that
raising the costs of fossil fuels, irrigation water and other limited
resources strongly encourages more ecient farming systems91. In
less-developed countries, targeted input subsidies and investment in
rural infrastructure are key nancial instruments. For example, sub-
sidizing organic nutrient inputs alongside mineral fertilizer inputs
for the poorest farmers can be an eective strategy for increasing
yields and building soils92.
Beyond organic
More than 40years aer Earl Butz’s comment, we are in a new era
of agriculture, as reected in the words of current US Secretary
of Agriculture Tom Vilsack: “Organic agriculture is one of the
REVIEW ARTICLE
NATURE PLANTS DOI: 10.1038/NPLANTS.2015.221
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6 NATURE PLANTS | VOL 2 | FEBRUARY 2016 | www.nature.com/natureplants
fastest growing segments of American agriculture and helps farmers
receive a higher price for their product as they strive to meet grow-
ing consumer demand”93. Moreover, organic agriculture has been
able to provide jobs, be protable, benet the soil and environment,
and support social interactions between farmers and consumers.
Although organic agriculture has an untapped potential role in
global food and ecosystem security, no one farming system alone
will safely feed the planet. Rather, a blend of organic and other inno-
vative farming systems, including agroforestry, integrated farming,
conservation agriculture, mixed crop and livestock, and still undis-
covered systems, will be needed for future global food and ecosys-
tem security. For example, integrated farming systems that blend
mostly organic with some conventional practices have been shown
to be more sustainable than conventional farming systems94,95 and
are likely to play a central role. Achieving global food and ecosys-
tem security requires more than just achieving sustainable farming
systems worldwide. We need to reduce food waste, improve food
distribution and access, stabilize the human population, eliminate
the conversion of food into fuel, and change consumption patterns
towards a more plant-based diet.
Equal adherence to all four sustainability goals of production,
environment, economics and social wellbeing does not limit but
encourages farmers and researchers to innovate. e challenge fac-
ing policymakers is to create an enabling environment for scaling-up
organic and other innovative farming systems to move towards truly
sustainable production systems. is is no small task, but the con-
sequences for food and ecosystem security could not be bigger. To
make this happen will require mobilizing the full arsenal of eective
policies, scientic and socioeconomic advances, farmer ingenuity
and public engagement.
Received 7 September 2015; accepted 17 December 2015;
published online 3 February 2016
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Economics
Wellbeing
Sustainable
agriculture
EnvironmentProduction
Figure 5 | Policy instruments for overcoming barriers to farmers adopting more sustainable farming systems. For any farm to be sustainable, it must
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conservation agriculture, integrated farming and mixed crop–livestock systems. A diversity of policy instruments is needed to overcome these barriers, and
can be categorized as financial, legal and knowledge-based instruments. Examples of these instruments are shown in the figure.
REVIEW ARTICLE NATURE PLANTS DOI: 10.1038/NPLANTS.2015.221
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Acknowledgements
J.M.W. is supported by NSF-IGERT (0903714) and USDA-NIFA (230470).
Author contributions
J.P.R. and J.M.W. contributed equally to the concept, outline and writing of the
manuscript, including generating the gures.
Additional information
Reprints and permissions information is available at www.nature.com/reprints.
Correspondence and requests for materials should be addressed to J.P.R.
Competing interests
e authors declare no competing nancial interests.
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