Urban agriculture is the practice of growing, preparing, and delivering food in cities. It also includes raising animals, growing fish, keeping bees, and planting gardens in urban areas. This is different from peri-urban agriculture, which happens in rural areas near cities. In many cities, expanding agriculture requires solving problems with soil pollution, especially from lead and other harmful metals, which can harm health and food safety.

Urban agriculture can exist in places with different levels of economic and social development. It may involve groups of people who grow organic food, enjoy cooking, or prefer eating locally grown food. These groups often work together and may receive support from local governments to help create sustainable cities. For others, the main reasons to practice urban agriculture are to ensure enough food, improve nutrition, and earn income. In both cases, urban agriculture can provide easier access to fresh vegetables, fruits, and meat. This helps increase food security and safety while reducing the distance food travels, which lowers greenhouse gas emissions and helps reduce the effects of climate change.

History

Some of the earliest evidence of urban agriculture comes from ancient Mesopotamian cultures. Farmers in these early cities set aside small areas of land inside city walls for farming. Around 3500 BC, in Persia’s semi-desert towns, communities used aqueducts to bring mountain water to oases, which helped grow large amounts of food using waste from the towns. The Hanging Gardens of Babylon are another well-known example, though some people may not be sure if they actually existed. In China, Xi’an has been continuously inhabited since at least 5000 BC, and its people have practiced urban agriculture at different times in history. At the Incan city of Machu Picchu, water was saved and reused through the city’s stepped buildings, and gardens were designed to capture sunlight to help plants grow longer. In the Americas, examples include the Aztecs’ chinampas, which were floating gardens in lakes that helped cities grow. In the Mississippi River area near St. Louis, the city of Cahokia relied on maize farming, and the Pueblo cultures in the Four Corners region used terraced plots on mesas for growing crops.

The idea of growing food in cities, instead of relying only on farms or imported food, has been used for a long time. It was common during wars, times of economic hardship, and even during times of plenty. In the early 1800s, Germany started allotment gardens to help poor people grow their own food.

In the United States, urban agriculture became more recognized during the 1893–1897 economic depression in Detroit. In 1894, Mayor Hazen S. Pingree asked people outside the city to let the government use their land to grow potatoes during the winter. These gardens, called “Pingree’s Potato Patches,” helped provide food and income during hard times. The success of this project inspired other American cities to try similar methods. By 1906, more than 75,000 schools in the U.S. had urban agriculture programs to give students and their families fresh food. However, it was not until World War I that urban agriculture became widespread in the U.S.

During World War I, growing food became important for national security. President Woodrow Wilson encouraged Americans to use any available space for growing food, which helped reduce the need for food to be sent overseas to soldiers. Groups like the National War Garden Committee promoted “victory gardens” with messages like “Sow the Seeds of Victory.” These gardens helped free up large farms to supply troops. In the U.S., victory gardens grew over 500 million pounds of food by 1919, and surplus food was sent to Europe and American military forces.

A similar practice happened during the Great Depression, when people grew food in gardens to help themselves and others during hard times. These efforts helped improve people’s moods and the economy. Over 2.8 million dollars’ worth of food was grown in subsistence gardens during the Depression. However, after the war, government support for victory gardens declined, and many gardens were repurposed for other uses.

During World War II, the U.S. government started a National Victory Garden Program to grow food in cities. These gardens were called the “first line of defense” for the country. The government encouraged people to grow food to help the war effort. About 5.5 million Americans participated, and they grew over nine million pounds of fruit and vegetables each year, which made up 44% of all food produced in the U.S. at the time. After the war, the government reduced support for urban agriculture as the need for wartime food decreased and industrial food systems became more common.

In the 1950s and 1960s, urban agriculture focused more on community efforts, especially by groups involved in social movements like the African-American Civil Rights movement. These groups used vacant land left behind after people moved from cities to suburbs. Some cities, like Syracuse, New York, supported urban agriculture to improve the appearance of these areas. Groups such as the Green Guerillas in New York City and P-Patch in Seattle helped shape urban farming practices in the 1970s, focusing on community development and environmental issues.

In the 1980s, urban agriculture expanded as more community programs were created. The U.S. government funded urban garden projects in 28 cities, which produced about $21 million worth of food. Though some gardens were repurposed, the overall trend was growth. In the 1990s, urban agriculture continued to expand, with more diverse goals and organizations involved.

From the 2000s through the 2020s, urban agriculture has grown even more. Some groups focus on helping immigrant communities with food security and cultural traditions, like Hmong American communities in various states. Others use urban farming as part of social justice efforts, such as in Wilmington, Delaware. Still others aim to fight food insecurity and help cities become more environmentally friendly. Many urban agriculture projects are now connected to food movements like local food networks and sustainable food systems. These movements try to change how food is grown, shared, and eaten by considering the needs of local communities and the environment.

Main types

There is no single word that describes agricultural areas in cities. Gardens and farms are the two main types, though they are not always easy to define. According to the United States Department of Agriculture (USDA), a farm is "any place from which $1,000 or more of agricultural products were produced and sold." In Europe, the term "city farm" is used to describe both gardens and farms. Any area where plants are grown can be considered an urban farm. The size of the area does not matter; it is about growing food in a personal garden or plot.

Many communities provide public spaces for community gardening, allowing people to grow plants for food, learning, and fun. In cities, small plots of land and rooftops are often used for this purpose. Community gardens help people learn about growing plants through hands-on experience. These gardens also help provide food to those in need. A well-known example is Seattle's P-Patch community gardening program. The grassroots permaculture movement has played a major role in the growth of urban farming worldwide. In the 1960s, community gardens were created in the United Kingdom, inspired by similar efforts in the United States. In 2010, Bristol's Severn Project was started with £2,500 and produces 34 tons of food each year, offering jobs to people facing challenges.

School gardens are an important part of urban agriculture. Interest in school gardens in the United States grew after observing successful agricultural education programs in Europe. Countries like France, Germany, Sweden, Belgium, and England had strong agricultural learning programs, which led to concerns that the United States was falling behind. The first school garden in the United States was established in Roxbury, Massachusetts, in the 1890s. The goal was to teach children about farming, as educators and government officials believed gardening helped improve students' education, health, and understanding of civic responsibilities. This movement, called the Nature Study movement, aimed to connect children with nature, teach agrarian values, and provide science lessons through observation. Cities often lack natural spaces for outdoor activities, making it harder for urban youth to connect with nature. As urban farming efforts expanded, such as the Detroit movement to turn empty lots into farms, school gardens became a way to teach children about growing food and connect them with the environment. In 1914, the Federal Bureau of Education officially supported school gardens as part of the school curriculum by creating the Division of Home and School Gardening.

One way urban farming begins is when family farms stay on their land as cities grow around them. City farms are agricultural areas in urban places where people grow food with plants and animals. These farms are often run by communities to improve relationships and teach people about farming. While the name suggests they are in cities, urban farms can also be in backyards or on rooftops. They are important for providing food to communities worldwide. City farms vary in size, from small plots in yards to large farms covering many acres. A 1996 United Nations report estimated that over 800 million people globally grow food and raise animals in cities. Many city farms rely on volunteers, while some have paid workers or partner with local governments.

An early example of a city farm was created in 1972 in Kentish Town, London. It includes both animals and gardens, inspired by children's farms in the Netherlands. Other city farms followed in London and the United Kingdom. In Australia, city farms exist in major cities like Melbourne, where the Collingwood Children's Farm was established in 1979 on land farmed since 1838.

In 2010, New York City opened the world's largest privately owned rooftop farm, followed by an even larger one in 2012. These projects were supported by city programs like the Green Roof Tax Abatement Program.

In the Philippines, many urban farms and other urban agriculture sites exist. Programs like the Philippine Urban Agriculture Network (PUAN) and the "Joy of Farming" initiative in Quezon City have helped create over 160 urban farms in backyards, churches, and community spaces. In Metro Manila's Taguig, a 300-square-meter urban farm built in 2020 helped the city during the COVID-19 pandemic. In Cebu, fishermen started a hybrid farm-to-table project to connect farming communities with markets.

In Singapore, hydroponic rooftop farms (which also use vertical farming) are growing. These farms aim to help communities that have been overlooked while producing pesticide-free food. Since Singapore imports most of its food, urban farming is seen as vital for national security, especially during the pandemic.

In Taiwan, city governments sometimes support urban agriculture to help the environment, such as through Taipei's Garden City Initiative. The program started small but became popular, with over 200 schools participating.

China is exploring urban farming to feed its growing population, especially in cities like Shanghai and the Pearl River Delta. Despite challenges, urban agriculture helps improve food and economic security.

Aquaponics is a farming method that combines growing fish (aquaculture) and plants (hydroponics) in a system that supports both. Fish waste provides nutrients for plants, and plants clean the water for fish. This system creates a balanced and self-sustaining environment.

Perspectives

The Urban Agriculture Network defines urban agriculture as the practice of growing, processing, and distributing food within cities. As more people move to urban areas, access to food becomes harder compared to rural regions. This problem affects poor communities the most, leading to unequal access to food and higher risks of malnutrition. Economic challenges in getting food are linked to how markets operate, which can limit choices to less healthy foods and create areas with little access to fresh food, called food deserts. Systems that govern poor urban communities often worsen issues like unemployment, poverty, and limited access to health, education, and food resources.

Many cities have large amounts of unused land due to population growth and abandoned homes. This land could help reduce food shortages. A study in Cleveland found that the city could grow enough fresh produce to meet all its needs, saving up to $115 million each year. Using rooftops in New York City could provide enough space to grow twice as much green vegetables as needed. Even more space could be used through methods like hydroponic farming or indoor food production. Growing food in cities also reduces waste. These projects would need money from private companies or government support.

The Council for Agricultural Science and Technology (CAST) includes environmental health, cleaning polluted areas, and recreation in its definition of urban agriculture. Modern planning and design often support this model because it fits with efforts to create sustainable cities. This definition can be interpreted in many ways across different cultures and times. It is often connected to policies that aim to build cities that are better for the environment.

Urban farms give people, especially city residents, a chance to learn about caring for the environment and working together. By growing food and connecting with nature, community gardens teach skills needed for democratic society. Running a farm requires group decisions, and the best results happen when community members take active roles.

About 20% to 30% of urban residents are involved in urban agriculture, but its environmental impact compared to regular farming is still being studied. A study by the University of Michigan found that urban farming uses six times more energy than traditional farming, though some crops like tomatoes have lower energy use when grown in cities. Ways to reduce negative effects include using rainwater and composting.

Access to healthy food is important for solving food shortages in cities. As more people live in urban areas, the need for fresh, safe food has grown. The Community Food Security Coalition (CFSC) defines food security as having enough nutritious food available and affordable. Areas with food security issues often rely on unhealthy, processed foods, which can lead to health problems like diabetes. This has led to the idea of food justice, which focuses on ensuring fair access to healthy, affordable food in communities affected by racial discrimination and unfair treatment.

Some studies have looked at how urban agriculture helps with food security and health. Urban agriculture is part of a larger effort to find better ways to grow food and fix problems like unequal access to fresh food and unfair practices in the food system. This effort involves many groups, including people facing food shortages, farmers, teachers, scientists, government leaders, and activists worldwide.

In Oakland, California, urban agriculture has grown because of new rules that make it easier for residents to grow food without special permits. Oakland has a history of unfair housing practices and limited access to grocery stores, which is common in communities of color. The increase in urban farming shows a focus on building strong communities. Activists in Oakland work to provide fresh food to those who need it while promoting community efforts. These programs combine education about food and the environment with community development, including school gardens and youth programs. Organizations like City Slicker Farms and Oakland Food Connection help residents get fresh food through community-supported agriculture and local markets.

Food security is linked to movements like food justice and food sovereignty. These movements use urban agriculture to address food needs in communities. Food sovereignty not only focuses on access to food but also on changing the power structures in the food system, including who controls food production and how decisions are made. It emphasizes community involvement and fair treatment.

Agroecology is a way of managing farms that helps achieve food sovereignty. Unlike traditional farming, agroecology focuses on healthy soil by connecting different parts of the environment. It values the well-being of farmers and consumers, traditional knowledge, and learning systems that involve many people. Agroecology supports social justice, gender equality, environmental protection, and public participation. For example, it has been used in movements demanding food grown without harmful chemicals.

Under agroecology, urban agriculture can help reduce environmental harm and support fair food systems.

Impacts and solutions

Urban and peri-urban agriculture (UPA) helps provide food, especially fresh fruits and vegetables, to people living in cities. It also creates jobs and income, which can improve food security and nutrition for urban residents.

UPA supports a city’s economy by growing, preparing, and selling food. This activity increases business opportunities, creates jobs, and lowers food costs while improving food quality. UPA helps people in cities access food and earn money, which can reduce long-term food shortages and sudden food crises. Long-term food shortages happen when food is too expensive or when people live in poverty. Sudden food crises occur when food delivery systems fail. UPA helps make food more affordable and provides food during emergencies. Studies show that food grown in urban gardens is worth about $200 to $500, after adjusting for inflation.

Urban agriculture can improve people’s mental and emotional health. It helps communities stay healthy, which benefits individuals’ feelings of happiness and well-being. Urban gardens often bring people together, encouraging positive interactions and stronger community connections. Gardens can also lower crime rates in neighborhoods. Many gardens become a source of pride for communities, helping people feel more connected. Urban agriculture increases community involvement through activities like workshops or planning groups focused on growing vegetables. These activities often involve hundreds of people.

When people work together in urban agriculture, they are more likely to be physically active. This can increase serotonin levels, similar to exercising at a gym. Walking or biking to gardens also adds to physical activity and the benefits of being outdoors.

UPA helps improve the lives of people living in and around cities. While most urban farming is informal, it has helped address food shortages in areas where access to food is unreliable. Growing food can make people feel more independent and confident. Families and small communities use empty land to grow food for their homes and sell extra food to local markets. This helps families earn more money and provides fresh, healthy food for their households. With the rise of farmers’ markets, more people can sell their produce and earn higher incomes.

Some urban farms help women find work, especially in places where women struggle to find jobs. Studies show that women often produce more food, meeting household needs and selling extra food for income.

Most urban agriculture happens on unused city land, which has raised concerns about who owns the land and how it is used. Organizations like the IDRC and FAO have created guidelines to help cities develop policies that support urban farming.

In the United States, about 42 million households grow food at home. Participation in farming by millennials increased by 63% from 2008 to 2013. Community gardening also tripled, with 3 million households involved. Urban agriculture brings people from different backgrounds together and gives healthcare workers chances to connect with patients. This makes community gardens important centers for neighborhoods.

The current food system requires a lot of energy to transport food. A study found that, on average, food travels 1,500 miles and uses 1 gallon of fuel for every 100 pounds of food. Local food reduces transportation energy and pollution. Another study estimated that using local food could save the same amount of carbon emissions as removing 16,191 cars from the road.

While urban agriculture can save money, energy costs depend on how and when people water plants.

Urban agriculture reduces a city’s carbon footprint by cutting down on transportation. Plants absorb carbon dioxide and release oxygen through photosynthesis. Choosing plants that stay green year-round can help remove more carbon from the air.

Reducing pollution like ozone and tiny particles in the air can improve health in cities. A study found that a rooftop with 2,000 square meters of grass could remove up to 4,000 kilograms of pollution, and one square meter of green roof could offset the pollution from one car per year.

Empty city lots are often used for illegal dumping or can collect polluted water, which harms public health. Growing food in these areas can clean the soil using a method called phytoremediation. Plants and microbes are used to remove harmful chemicals like heavy metals, inorganic compounds, and organic pollutants from the soil. This process is eco-friendly, cost-effective, and uses little energy.

Implementation

Creating a community-based system for urban farming means setting up local ways to grow food, prepare it, and deliver it from farmers to people who buy it.

To help grow food, cities have started community farming projects. Some groups work together to care for shared farms on public land, similar to the Boston Common from the 1700s. One example is the Collingwood Children's Farm in Melbourne, Australia. Other projects use the allotment garden model, where individuals tend their own plots in a shared garden space, often using shared tools and facilities. Seattle's P-Patch Gardens, South Central Farm in Los Angeles, and Food Roof Farm in St. Louis use this model. Some urban gardeners grow food in their own yards or on building rooftops. Garden sharing programs match people who grow food with available land, like residential yards. Rooftop gardens let city residents keep green spaces without needing unused land. Rooftop farms use empty industrial rooftops to grow food, creating jobs and income. Worldwide, projects aim to turn cities into places where food is grown continuously by using empty land and setting up gardens.

Processing food at the community level happens by sharing tools and resources in central places. In Detroit, the Garden Resource Program Collaborative has shared tool storage areas in different parts of the city. These areas provide tools, compost, seeds, and gardening lessons to local gardeners. The program also helps gardeners by sharing young plants, offering education on gardening and food issues, and connecting them through events like group meetings and tours. In Brazil, the "Cities Without Hunger" program has created public policies to turn unused areas into places for growing food and improve community green spaces.

Farmers' markets, like the one in Los Angeles, are places where farmers sell food directly to buyers. Large cities often open these markets on weekends and one weekday. For example, the Boulevard Richard-Lenoir market in Paris is open on Sundays and Thursdays. To help people rely on local food and support farmers' jobs, markets should be open regularly. The Los Angeles Farmers' Market is open every day and connects local stores to offer a variety of food. Its location in downtown Los Angeles makes it easy for many sellers and buyers to meet.

Benefits

Urban agriculture (UA) offers many advantages for cities that use this practice. When cities change from being places that only use food to places that grow food, it helps the environment, improves health, and reduces poverty.

• UA creates systems where food is used and waste is reused in the same area, instead of sending waste to rural areas.
• Wastewater and organic waste can be turned into resources for growing food. Wastewater can be used to water plants, and organic waste can be used as fertilizer.
• Empty spaces in cities can be used for farming instead of staying unused.
• Using wastewater for farming helps manage water better and increases the amount of fresh water available for drinking and daily use.
• UA helps protect natural environments by preventing them from being turned into farmland.
• Farming in cities saves energy, such as the energy used to transport food from rural areas to cities.
• Growing food locally reduces costs for transportation, storage, and food loss, which lowers the price of food.
• UA improves the quality of the city by adding green spaces, which reduces pollution.
• Farming in cities makes the environment healthier, which benefits people who live there.
• UA helps fight hunger and malnutrition by providing food to people who live in poverty.

Many people in cities who are poor grow food in urban areas. In developing countries, most urban farming is done for personal use, with extra food sold in markets. The Food and Agriculture Organization of the United Nations (FAO) reports that poor urban families spend 60–80% of their income on food, making them more affected by rising food prices.

• UA provides food and reduces household spending, allowing families to use more money for other needs.
• Extra food from urban farming can be sold in local markets, giving the poor more income.

Community centers and gardens teach people that farming is an important part of city life. The Florida House Institute for Sustainable Development in Sarasota, Florida, is a public center where people can learn about and test ideas for sustainable living. Centers like Florida House help cities include farming in daily life by offering spaces to learn about food production.

Urban farms also teach children about healthy eating and physical activity.

Trade-offs

• Space in cities is limited, making it costly and hard to find.
• Using untreated wastewater to water crops in cities can spread diseases caused by water.
• Research shows that urban gardens can improve air quality, but more cars in cities increase pollution. This pollution leads to more insect pests that harm plants in urban farming. Pollution also changes plant structures, making them more attractive to pests. This reduces the amount of food produced in urban gardens.
• Studies show that wheat grown in cities loses nutritional value when exposed to high levels of nitrogen dioxide and sulfur dioxide. This issue is especially serious in developing countries, where sulfur dioxide levels are high and many people depend on urban farming for food. These findings may also affect other important crops grown in cities.
• Farming on land polluted with harmful metals, such as lead, can harm human health. Risks come from working on polluted land and eating food grown in it.

City policies aimed at greening areas can sometimes conflict. For example, policies that encourage planting trees may not support vegetable gardening because trees cast heavy shade. However, some cities, like Portland, Oregon, and Davenport, Iowa, are promoting fruit trees (planted as street trees or in parks) to achieve both greening goals and food production.