A community garden is a piece of land gardened or cultivated by a group of people individually or collectively. Normally in community gardens, the land is divided into individual plots. Each individual gardener is responsible for their own plot, and the yield or production belongs to them. In collective gardens, the piece of land is not divided. A group of people cultivates it together, and the harvest belongs to all participants. Around the world, community gardens exist in various forms; they can be located near neighborhoods or on balconies and rooftops. Their size can vary greatly from one to another. Depending on the location can determine the price of community gardens. Many community gardens also function as informal educational spaces, where volunteers teach newcomers basic gardening skills and sustainable growing practices.

Community gardens have experienced three waves of major development in North America. The earliest wave of community gardens development coincided with the Industrial Revolution and rapid urbanization process in Europe and North America; they were then called 'Jardin d'ouvrier' (or workers' garden). The second wave of community garden development happened during the WWI and WWII; they were part of "Liberty Gardens" and "Victory Gardens" respectively. The most recent wave of community garden development happened in the 1970s during the OPEC crisis, results of grassroots movement in quest for available land to combat against food insecurity.

More recently, community gardens have seen a global resurgence. This may be related to several issues faced by the global population in the 21st century, such as ecological crisis, climate change and the new sanitary crisis. Community gardens contribute to the urban agriculture movement and the requests from citizens for more community gardens has been surging in recent years. Community gardens are also accessible in over 190 + countries/regions

Background According to Marin Master Gardeners, "a community garden is any piece of land gardened by a group of people, utilizing either individual or shared plots on private or public land". Community gardens provide fresh products and plants as well as contribute to a sense of community and connection to the environment and an opportunity for satisfying labor and neighborhood improvement. They are publicly functioning in terms of ownership, access, and management, as well as typically owned in trust by local governments or not for profit associations.

Community gardens vary widely throughout the world. In North America, community gardens range from "victory garden" areas where people grow small plots of vegetables, to large "greening" projects to preserve natural areas, to large parcels where the gardeners produce much more than they can use themselves. Non-profits in many major cities offer assistance to low-income families, children's groups, and community organizations by helping them develop and grow their own gardens. In the UK and the rest of Europe, the similar "allotment gardens" can have dozens of plots, each measuring hundreds of square meters and rented by the same family for generations. In the developing world, commonly held land for small gardens is a familiar part of the landscape, even in urban areas, where they may function as market gardens.

Community gardens are often used in cities to provide fresh vegetables and fruits in "food deserts", which are urban neighborhoods where grocery stores are rare and residents may rely on processed food from convenience stores, gas stations, and fast-food restaurants.

Some writers have proposed re-framing the concept of "food deserts" as "food apartheid," emphasizing that neighborhoods lacking access to healthy food have been racially oppressed through segregation, redlining, and limited access to land. Some Black, Indigenous, and people of color have supported self-sustaining community gardens, recognizing that their liberation requires access to both land and healthy food.

Community gardens may help alleviate one effect of climate change, which is expected to cause a global decline in agricultural output, making fresh produce increasingly unaffordable.Harris, E (2009). "The role of community gardens in creating healthy communities", Australian Planner, v. 46, no. 2 (June 2009) pp. 24–27. Community gardens are also an increasingly popular method of changing the built environment in order to promote health and wellness in the face of urbanization. The built environment has a wide range of positive and negative effects on the people who work, live, and play in a given area, including a person's chance of developing obesity.Xu, Y., & Wang, F. (2015). Built environment and obesity by urbanicity in the U.S. Health & Place, 34, 19–29. Community gardens encourage an urban community's food security, allowing citizens to grow their own food or for others to donate what they have grown. Advocates say locally grown food decreases a community's reliance on fossil fuels for transport of food from large agricultural areas and reduces a society's overall use of fossil fuels to drive in agricultural machinery.: Kishler, Les. Opinion: community gardens are a serious answer to food supplies, health (2010, March 18) San Jose Mercury News.

Community gardens improve users’ health through increased fresh vegetable consumption and providing a venue for exercise.

The gardens also combat two forms of alienation that plague modern urban life: they reconnect urban gardeners with the source of their food and reduce isolation by fostering a sense of community. Community gardens provide other social benefits, such as the sharing of food production knowledge with the wider community and safer living spaces.Harris, E (2009). Active communities experience less crime and vandalism.Melville Court, Chatham, Kent," Moiser, Steve, Landscape Design, no306 (Dec. 2001/Jan. 2002) p. 34.

Ownership Land for a community garden can be publicly or privately held. In North America, often abandoned vacant lots are cleaned up and used as gardens. Because of their health and recreational benefits, community gardens may be included in public parks, similar to ball fields or playgrounds. Historically, community gardens have also served to provide food during wartime or periods of economic depression. Access to land and security of land tenure remains a major challenge for community gardeners worldwide, since in most cases the gardeners themselves do not own or control the land directly.Visionaries and planners : the garden city movement and the modern community, Stanley Buder. New York: Oxford University Press, 1990.

Some gardens are cultivated collectively, with everyone working together, while others are divided into individual plots, each managed by a different gardener, group, or family. Many community gardens include both common areas with shared upkeep and individual or family plots. Though communal areas are successful in some cases, in others there is a tragedy of the commons, which results in uneven workload on participants, and sometimes demoralization, neglect, and abandonment of the communal model. Some relate this to the largely unsuccessful history of collective farming.

Unlike public parks, whether a community garden is open to the general public is dependent upon the lease agreements with the management body of the park and the community garden membership. Open- or closed-gate policies vary from garden to garden. Community gardens are managed and maintained by the gardeners themselves, rather than tended only by a professional staff. A second difference is food production: Unlike parks, where plantings are ornamental (or more recently ecological), community gardens are usually focused on food production.Selected factors influencing the success of a community garden, by Gordon Arthur Clark. Kansas State University, 1980.

Types of gardens There are multiple types of community gardens. Neighborhood gardens Residential Gardens Institutional Gardens Demonstration Gardens

Plot size In Britain, the 1922 Allotment act specifies "an allotment not exceeding 40 [square] poles in extent"; since a rod, pole or perch is 5.5 yards in length, 40 square rods is 1210 square yards or 10890 square feet (equivalent to a large plot of 90 ft x 121 ft). In practice, plot sizes vary; Lewisham offers plots with an "average size" of "125 meters square".

In America there is no standardized plot size. For example, plots of 3 m × 6 m (10 ft × 20 ft = 200 square feet) and 3 m x 4.5 m (10 ft x 15 ft) are listed in Alaska. Montgomery Parks in Maryland lists plots of 200, 300, 400 and 625 square feet. In Canada, plots of 20 ft x 20 ft and 10 ft x 10 ft, as well as smaller "raised beds", are listed in Vancouver.

Location Community gardens may be found in neighborhoods and on the grounds of schools, hospitals, and residential housing. The location of a community garden is a critical factor in how often the community garden is used and who visits it. Exposure to a community garden is much more likely for an individual if they are able to walk or drive to the location, as opposed to public transportation. The length of travel time is also a factor. Those who live within a 15-minute or less travel distance is more likely to visit a community garden as compared to those with a longer travel time. Such statistics should be taken into consideration when choosing a location for a community garden for a target population.

The site location should also be considered for its soil conditions as well as sun conditions. An area with a fair amount of morning sunlight and shade in the afternoon is most ideal. While specifics vary from plant to plant, most do well with 6 to 8 full hours of sunlight.

When considering a location, areas near industrial zones may require soil testing for contaminants. If soil is safe, the composition should be loose and well-draining. However, if the soil at the location cannot be used, synthetic soil may also be used in raised gardens beds or containers.

Plant choice and physical layout Food production is central to most community and allotment gardens. However, restoration of natural areas and native plant gardens are also popular, as are "art" gardens. Many gardens include diverse planting elements, combining individual plots with features such as small orchards, herb gardens, and butterfly gardens. Individual plots are often highly diverse, incorporating a mix of flowers and vegetables.

Gardeners often grow in-ground—this type of garden contrasts most with an urban environment. Gardeners may also grow in raised beds, or in boxes, sometimes on top of a paved area. Gardens may include raised for use by people who cannot bend or work directly on the ground.

Regardless of plant choice, planning out the garden layout beforehand will help avoid problems down the line. According to the Arizona Master Gardener Manual, taking measurements of the garden size, sunlight locations and planted crops vs. yield quantity, will ensure a detailed record that helps when making decisions for the coming years. Other considerations when laying out a plot are efficient use of space by using trellises for climbing crops, plant location so that taller plants (like sunflowers) do not block needed sunlight to shorter plants and grouping plants that have similar life cycles close together.

Group and leadership selection Community gardeners in North America may be of any cultural background, young or old, new gardeners or seasoned growers, rich or poor. Because of this diversity, when gardeners share their harvest, they often learn about cultural foods created from the plants grown by other gardeners.