Fujio Kato’s family has been farming in Tokyo for over ten generations. Beginning sometime in the Edo era over 300 years ago, the Kato family has been producing daikon radish and other vegetables that have helped nourish Tokyo’s growing urban population. Fujio continues to produce vegetables but now sells them in a vending machine outside his green (hoop) house in a Tokyo suburb.
Fujio’s experience is not unique. Urban farmers across the world play a critical role in feeding consumers, especially with fresh fruits and vegetables. Globally, urban farming accounts for 15 percent of the total agricultural land in the world, and up to 40 percent of all cropland when all agriculture within 20 kilometres of cities is included. Along with other urban farming systems like Istanbul’s (Turkey) bostans, urban agriculture represents a critical part of our natural heritage.
But urban farming is threatened by urbanization and today’s cities that are growing twice as fast in land area than in population. Urban expansion is projected to destroy roughly 2 percent of global croplands by 2030, 80 percent occurring in Asia and Africa. This is a problem since urban farmland is more than twice as productive as national averages. This tremendous loss of land will result in lost livelihoods and contribute to carbon emissions by replacing natural areas with roads and buildings.
A growing number of cities throughout the world are beginning to take action to support urban farming. They recognize that there is huge potential for urban farming to contribute to many food system and urban development goals. First, urban farming can be an important source of affordable, nutritious food, particularly fresh fruit and vegetables, which are critically important to good health and nutrition. In many cities throughout Asia, urban and peri-urban horticulture production supplies up to 90 percent of the vegetables consumed in cities, particularly green leafy varieties.
Urban farming, together with the preservation of urban forests and protection of cities’ green areas contribute to lower urban temperatures; provide natural drainage systems to reduce flooding. When floods and other disasters cut food supplies to cities, urban farming can provide a small but critical source of food.
Urban farming systems can also use used nonindustrial, properly treated wastewater as a source of irrigation water, replacing the dangerous use of untreated and unsafe urban wastewater, and reducing disposal costs for cities. Cities are finding ways to reduce diverse urban farming risks from air and soil pollutants, chemical exposure through testing, treatment and management.
Just as Japanese farmers composted human waste to fertilize fields over three hundred years ago, cities and private companies can process human and other organic waste to produce safe, nutrient-rich compost/fertilizer in powder or pellets. Urban farming plays a key role in linking food, energy and water. Use of food waste to produce energy (cogeneration using biogas from anaerobic digestion facilities) can decrease energy needs while reducing adverse environmental impacts from waste.
Advances in technology are allowing farmers to grow food in multiple ways – whether in vacant urban lots, in greenhouses, on rooftops, in shipping containers or burlap bags or indoor multi-story vertical farms. New systems allow food to be grown with or without soil and irrigated through a nutrient solution or misting sprayers. Options are available for families, small businesses or big companies. These new systems are very productive. Hydroponic production systems – that grow food in water (without soil) – that are used in greenhouses, vertical farms and container farms are 9, 7 and 4 times more productive in producing leafy green vegetables (pounds/foot2) than conventional agriculture.
To benefit from urban farming, cities and countries need updated urban, agriculture and food policies that regulate access to land and allowing new types of farming. Urban farmers also need technical knowledge, skills and support to use new production methods and to sell their food in changing city markets, grocery stores and restaurants. With proper support, urban farming can complement traditional agriculture production in rural areas to help cities and countries meet the needs of their citizens with fresh, safe food.
FAO Investment Centre