It is estimated that in the early 1800s, only about 3% of the world’s one billion people lived in cities. Until this time, a vast majority of the human population labored in agriculture on small farms. Today, in a world of more than 7 billion people, over half of the population resides in urban areas and a shrinking minority are small farmers. Rapid urban population growth has been concentrated in marginal and peripheral areas of cities, many of which are slums. Urban poverty, unemployment, food insecurity, and malnutrition are growing dangers, particularly in developing countries.

In countries like the United States, the shift away from small farms has been more extreme. In the 1800s, about 75% of the population was employed in agriculture. Today, that figure is about 2%. This shift can largely be attributed to the rise of industrial agricultural practices in the 20th century that resulted from the development of new technologies and world markets. Although these practices created short-term increases in agricultural production and crop yields, they have also caused long-term ecological impacts such as soil degradation and erosion, water pollution, aquifer depletion, loss of biodiversity and habitat alteration — all which threaten the future viability of agriculture altogether. The use of agrochemicals such as pesticides and fertilizers have also been shown to have negative human and environmental health effects.

Access to food is still a major problem in United States, where 26.5 million people are living in food deserts — mostly in urban areas where fresh groceries are unavailable and fast food is the only option. This is causing disastrous health effects, and many are dying of preventable diseases. The rate of obesity the United States is now the highest in the world, having grown from 13% of American adults in 1962 to 35.7% of American adults and 17% of American children. If obesity rates continue to rise, it has been projected that the increase in illnesses such as diabetes, chronic heart disease and strokes could cost the United States an additional $66 billion in obesity-related medical costs each year (on top of the existing annual $147 billion).

Urban Agriculture

Addressing these threats requires the planning and design of adequate food supply and distribution systems. As a complement to the implementation of environmentally responsible practices in rural agriculture, urban agriculture will be a key component of any successful strategy. As the world’s cities grow, the role of urban agriculture becomes increasingly important. It can take several forms — community farms, commercial farms, institutional farms, or community gardens.

The obvious constraints of a city environment often raise questions about the limits of urban farming. But these same constraints have also helped inspire creative techniques and practices such as biointensive agriculture, rooftop gardening, indoor growing, and aquaponic systems. And even though cities are dense, there is often more vacant land suitable for farming than one might assume (see sections below about Los Angeles, Detroit, and New York). Urban agriculture can supply much of the food cities require without expensive transport costs.

The Benefits of Urban Agriculture

In addition to food production, urban agriculture also supports related economic activities and provides many environmental services. Indeed, the benefits of urban agriculture to cities are numerous and range across many areas including:

Health

• Access to healthy food
• Food health literacy
• Healthy eating
• Physical activity

Social

• Food security
• Empowerment and mobilization
• Youth development and education
• Safe spaces

Economic

• Local economic stimulation
• Job growth
• Job readiness
• Food affordability

Ecological

• Stewardship
• Conservation
• Storm water management
• Biodegradable waste management
• Soil improvement
• Biodiversity and habitat improvement

(For more detail, check out this graphic put together by Five Borough Farm of New York City that demonstrates how urban agriculture can positively transform communities)

Cities, however, tend to not have policies and legislation in place that effectively support urban agriculture, let alone allow for it at all. Often the case is exactly the opposite; zoning, licensing, and permitting issues can be obstacles to growing or selling fruits and vegetables in urban areas. Without recognition of legitimacy at the city level, strong grassroots efforts have been necessary to build the foundation for the expansion of urban agriculture.

Challenges and Solutions — Los Angeles and Detroit

Take South Central Los Angeles for example. When Ron Finley of LA Green Grounds decided to plant a ‘food forest’ in the parkway next to the sidewalk in front of his home, all on a volunteer basis, the city eventually gave him a citation (and subsequently a warrant) telling him he needed to remove his garden. However, the determined Finley was able to reverse the decision with the support of a petition signed by more than 900 individuals, including his city council member who called him to personally applaud his efforts. As Finley asks in his TED talk about his work and the art of guerilla gardening: why wouldn’t the city be happy about this type of project? Los Angeles owns about 26 square miles of vacant lots, the most owned by any city in the country. To paint a picture of that capacity, Finley points out that is enough space to grow nearly 725 million tomato plants.

Detroit is another city in which the grassroots urban agriculture movement is strong. There are now at least 355 community gardens in Detroit, more per capita and per square mile than in any other city in the United States. Programs such as the Garden Resource Collaborative, Earthworks Urban Farm, and Detroit Black Community Food Security Network help support urban agriculture by training, organizing, demonstrating, and providing resources. These kinds of programs have contributed to establishing and supporting the hundreds of backyard, community, school, and market gardens that collectively produce several hundred tons of food per year.

Similarly to Los Angeles, the city of Detroit is in control of a large amount of vacant parcels. A specialist from Michigan State University has estimated that developing just 4,000 acres of land (a small percent of the vacant land) using urban agriculture could provide Detroit residents with 75% of their vegetables and 40% of their fruits. Michigan State itself plans to invest $1.5 million over the next three years into a program called MetroFoodPlus Innovation Cluster, which has the goal of creating new and sustainable models for economic development and food security in and around Detroit.

5,000 Acres in New York City

MSU is not the only institute of higher education investing resources in researching and developing the potential of urban agriculture. Last year, the Urban Design Lab at the Earth Institute of Columbia University released a comprehensive report entitled “The Potential for Urban Agriculture in New York City: Growing Capacity, Food Security, & Green Infrastructure”. The report identifies almost 5,000 acres of vacant land likely to be suitable for farming in the five boroughs, the equivalent of six times the area of Central Park. In addition to this land, there are many other potential sites, including over 1,000 acres of NYCHA green space, underutilized open spaces, and Greenstreets.

Some other key findings of the report include:

• There is significant potential for urban agriculture to provide critical environmental services to the city through stormwater runoff mitigation, soil remediation, and energy use reduction.
• Urban agriculture can play an important role in community development.
• Intensive growing methods adapted to urban spaces can result in yields per acre which greatly exceed those of conventional production techniques.
• NYC’s rooftops are a vast, underused resource that could be transformed for food production.
• Urban farmers are establishing viable businesses by taking advantage of multiple revenue streams.
• Existing infrastructure has the potential to support the expansion of urban agriculture.
• Urban agriculture functions as a catalyst for larger food system transformations.
• Bureaucratic challenges are a major barrier to the expansion of urban farming

As previously mentioned, this last problem is common to many cities across the country. Some city governments, however, have taken notice of the need to update their policies to allow for urban agriculture to grow into its full potential. In San Francisco in 2011, the Board of Supervisors passed legislation that amended the zoning code to allow agricultural activities in all parts of the city, lowered permit fees, and defined the parameters by which urban agriculturalists can sell their products.

Other cities are also becoming conscious of the need to update their codes in order to welcome the benefits of urban agriculture. The Austin Sustainable Food Policy Board recently held several working group sessions on Urban Farms Process and Code Coordination in an effort to gather recommendations and best practices for drafting new provisions for the code later this month.

These are signs that cities are beginning to recognize the important role urban agriculture will play in the future of human life on our planet. For urban agriculture to fully blossom, however, governments will need to play a more active role in support of its expansion. Considering the many benefits it has to offer, why wouldn’t they?