system. in accra, men are primarily responsible for the labors of urban farming. india economic development in mumbai brought a growth in population caused mainly by the migration of laborers from other regions of the country. the number of residents in the city increased more than twelve times in the last century. greater mumbai, formed by city island and salsette island, is the largest city in india with a population of 16.4 million, according to data collected by the census of 2001. mumbai is one of the densest cities in the world, 48,215 persons per km² and 16,082 per km² in suburban areas. in this scenario, urban agriculture seems unlikely to be put into practice since it must compete with real estate developers for the access and use of vacant lots. alternative farming methods have emerged as a response to the scarcity of land, water, and economic resources employed in upa. dr. doshi's city garden methods are revolutionary for being appropriate to apply in reduced spaces as terraces and balconies, even on civil construction walls, and for not requiring big investments in capital or long hours of work. his farming practice is purely organic and is mainly directed to domestic consumption. his gardening tools are composed of materials available in the local environment: sugarcane waste, polyethylene bags, tires, containers and cylinders, and soil. the containers and bags (open at both ends) are filled with the sugarcane stalks, compost, and garden soil, which make possible the use of a minimal quantity of water is compared to open fields. doshi states that solar energy can replace soil in cities. he also recommends the idea of chain planning, or growing plants in intervals and in small quantities rather than at once and in large amounts. he has grown different types of fruit such as mangos, figs, guavas, bananas and sugarcane stalks in his terrace of 1,200 sq ft (110 m2) in bandra. the concept of city farming developed by doshi consumes the entire household's organic waste. he subsequently makes the household self-sufficient in the provision of food: 5 kilograms (11 lb) of fruits and vegetables are produced daily for 300 days a year. the main objectives of a pilot project at city farm at rosary high school, dockyard road, were to promote economic support for street children, beautify the city landscape, supply locally produced organic food to urban dwellers (mainly those residing in slums), and to manage organic waste in a sustainable city. the project was conducted in the rosary school, in mumbai, with the participation of street children during 2004. a city farm was created in a terrace area of 400 sq ft (37 m2). the participants were trained in urban farming techniques. the farm produced vegetables, fruits, and flowers. the idea has spread the concept of a city farm to other schools in the city. the mumbai port trust (mbpt) central kitchen distributes food to approximately 3,000 employees daily, generating important amounts of organic disposal. a terrace garden created by the staff recycles 90% of this waste in the production of vegetables and fruits. preeti patil, who is the catering officer at the mbpt explains the purpose of the enterprise: mumbai port trust has developed an organic farm on the terrace of its central kitchen, which is an area of approximately 3,000 sq ft (280 m2). the activity of city farming was started initially to dispose of kitchen organic waste in an eco-friendly way. staff members, after their daily work in the kitchen, tend the garden, which has about 150 plants. new zealand kaicycle urban farm in wellington, new zealand an urban farm called kaicycle in the capital city wellington was established in 2015. it started as a way of composting local food waste, food scraps are collected by bicycle. their criteria includes organic waste of up to 60 litres per week from local households and business. their purpose is "diverting food waste from landfill and recycling these nutrients back into local soils". they garden on their urban farm with the compost they make and invite volunteers to help regularly. they sell some of the produce which helps pay for the composting operations, they also share it with volunteers and donate to community food projects. in 2020 it joined a new network of composting hubs managed by the sustainability trust. singapore since the city state currently only produces less than 10% of food requirements locally, the singaporean government has actively backed starters of urban farms in the city state with grants. as part of singapore's "30 by 30" plan to produce 30% of the island state's food locally by 2030, the urban redevelopment authority has actively encouraged the growing of commercial crops on top of singapore's iconic hdb buildings, as well as in skyscrapers. singapore's urban farming segment had an estimated market value of 22 million singapore dollars in 2019. the website of the urban redevelopment authority gives some examples of singapore's successes with urban farming: some local examples featured include sky greens’ innovative 9-metre tall system that allows vegetables to grow outdoors and vertically; sustenir agriculture’s indoor controlled environment agriculture (cea) farm that enables it to control all aspects of the environment to optimise crop growth; and apollo aquaculture group’s three-tier vertical recirculating aquaculture system that lets it grow pearl grouper, coral trout, and white shrimp indoors on multiple levels. taiwan shanlong vegetable park in taiwan in matsu islands, the local government established a vegetable farmland at the town center of nangan. thailand in early 2000, urban gardens were started under the direction of the ngo, thailand environment institute (tei), to help achieve the bangkok metropolitan administrations (bma) priority to "green" thailand. with a population of 12 million and 39% of the land in the city vacant due to rapid expansion of the 1960s–80s bangkok is a testbed for urban gardens centered on community involvement. the two urban gardens initiated by tei are in bangkok noi and bangkapi and the main tasks were stated as: teach members of the communities the benefits of urban green space. create the social framework to plan, implement, and maintain the urban green space. create a process of a method to balance the needs of the community with the needs of the larger environmental concerns. while the goals of the ngo are important in a global context, the community goals are being met through the work of forming the urban gardens themselves. in this sense, the creation, implementation, and maintenance of urban gardens are highly determined by the desires of the communities involved. however, the criteria by which tei measured their success illustrates the scope of benefits to a community which practices urban agriculture. tei's success indicators were: establishing an urban green plan community capacity building poverty reduction links with government developing a model for other communities united kingdom todmorden is a town of 17,000 inhabitants in yorkshire, united kingdom with a successful urban agriculture model. the project, which began in 2008, has meant that food crops have been planted at forty locations throughout the town. the produce is all free, the work is done by volunteers, and passers-by and visitors are invited to pick and use the products. some todmorden plots have been permission plots while others have been examples of guerilla gardening. all are "propaganda gardens" promoting locals to consider growing local, to eat seasonal, to consider the provenance of their food, and to enjoy fresh. there are food plots in the street, in the health center car park, at the rail station, in the police station, in the cemetery, and in all the town's schools. nationwide survey findings according to the usda, a farm is defined as a location that produces and sells at least $1,000 worth of products. a study conducted on urban farms in 2012 surveyed over 315 farms identified as urban. of those, over 32% were found in the northeast, more than 26% in the south, 22% in the west, and less than 19% in the midwest. the survey found that most urban farms in the united states are structured as either non-profit or solely owned. urban farms typically use techniques that allow them to produce intensively on a small land. mainly, these practices include raised beds, greenhouse, and container gardens. of the products made, an overwhelming majority of urban farms focus on fresh vegetables, followed by herbs and flowers. if an urban farm focuses on animals, the primary animal is hens. bees and sheep are the second most common urban farm animals. almost half of the urban farms that participated in the survey made a total gross sale adding to less than $10,000. the majority of these sales coming from farmer's markets, community-upported agriculture (csa), and restaurants. not even 5% of the urban farms could be considered according to total gross sales statistics. most urban farms agree on the main challenges that they face; production costs, managing pests, managing weeds, and climate. they also see profitability, financing, and farm labor as big challenges of managing an urban farm. new york garden of adam purple, lower east-side, new york city, 1984 new york city has become a laboratory for urban agriculture within the last decade. the city began to make significant strides in 2007 with the founding of the mayor's office of food policy, although urban agricultural initiatives are sponsored by other city agencies, too. the city's department of environmental protection, for example, offers a grant program for private property owners in combined sewer areas of new york city. the minimum requirement for grantees is to manage 1" of stormwater runoff from the contributing impervious area. eligible projects to manage water runoff include green roofs, rooftop farms, and rainwater harvesting on private property in combined sewer areas. the grant program has allowed new york city to build some of the world's largest rooftop farms. urban agriculture is especially important in new york city as many low-income residents suffer from high rates of obesity and diabetes and limited sources of fresh produce. the city and local nonprofit groups have been providing land, training and financial encouragement, but the impetus in urban farming has really come from the farmers, who often volunteer when their regular workday is done. one nyc urban agriculture initiative targeted at low-income residents is the farms at nycha project. the program is a city-partnership placed in 12 neighborhoods that is intended to expand access to healthy food, promote healthy public housing committees and to develop young leadership. another program comes from grow to learn, which provides opportunities for public school students to learn through urban farming. the program has grown to over 800 gardens since 2010. there are various types of agricultural systems in new york city. two alternate means of growing are: rooftop gardens and hydroponic (soil-less) growing. the new york times wrote an article about one of manhattan's first gardens which incorporate both these techniques. additionally, some urban gardeners have used empty lots to start a community or urban gardens. however, the soil must be tested for heavy contamination in city soil because of vehicle exhaust and remnants of old construction. regardless, there are hundreds of urban gardens across new york city. controlled environment agricultural systems are also becoming increasingly common. according to one study, controlled environment agriculture systems in new york city have increased access to produce for some low-income communities and have created green-sector job opportunities. proponents of hydroponic systems in particular have argued that producers like gotham greens have allowed city residents access to high nutrient produce within hours of its harvest. lastly, the city also has a composting program, which is available to gardeners, farmers, and residents. one group, greenthumb, provides free seedlings. another program, the city farms project operated by the nonprofit just food, offers courses on growing and selling food. california in response to the recession of 2008, a coalition of community-based organizations, farmers, and academic institutions in california's pomona valley formed the pomona valley urban agriculture initiative. after the passage of the north american free trade agreement, cheap grain from the united states flooded mexico, driving peasant farmers off of their land. many immigrated to the pomona valley and found work in the construction industry. with the 2008 recession, the construction industry also suffered in the region. it is unlikely to regain its former strength because