Land for a community garden can be publicly or privately held. One strong tradition in American community gardening in urban areas is cleaning up abandoned vacant lots and turning them into productive gardens. Alternatively, community gardens can be seen as a health or recreational amenity and 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 and their supporters throughout the world, since in most cases the gardeners themselves do not own or control the land directly.
Some gardens are grown collectively, with everyone working together; others are split into clearly divided plots, each managed by a different gardener (or group or family). Many community gardens have both "common areas" with shared upkeep and individual/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 community gardens are 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. However, in a key difference, community gardens are managed and maintained with the active participation of 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 often encourage food production by providing gardeners a place to grow vegetables and other crops. To facilitate this, a community garden may be divided into individual plots or tended in a communal fashion, depending on the size and quality of a garden and the members involved.
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