Guerrilla gardening is gardening on another person's land without permission. It encompases a very diverse range of people and motivations, from the enthusiastic gardener who spills over their legal boundaries to the highly political gardener who seeks to provoke change through direct action. It has implications for land rights, land reform. The land that is guerrilla gardened is usually abandoned or neglected by its legal owner and the guerrilla gardeners take it over ("squat") to grow plants. Guerrilla gardeners believe in re-considering land ownership in order to reclaim land from perceived neglect or misuse and assign a new purpose to it.
Some guerrilla gardeners carry out their actions at night, in relative secrecy, to sow and tend a new vegetable patch or flower garden. Some garden at more visible hours to be seen by their community. It has grown into a form of proactive activism or pro-activism.
The earliest record of the term guerrilla gardening being used was by Liz Christy and her Green Guerrilla group in 1973 in the Bowery Houston area of New York. They transformed a derelict private lot into a garden. The space is still cared for by volunteers but now enjoys the protection of the city's parks department. Two celebrated guerrilla gardeners, active prior to the coining of the term, were Gerrard Winstanley, of the Diggers in Surrey, England (1649), and John "Appleseed" Chapman in Ohio, USA (1801).
Guerrilla gardening takes place in many parts of the world - more than thirty countries are documented  and evidence can be found online in numerous guerrilla gardening social networking groups and in the Community pages of GuerrillaGardening.org .
The term guerrilla gardening is applied by some quite loosely to describe different forms of radical gardening. This includes gardening as an entirely political gesture rather than one with genuine horticultural ambition, such as the London May Day protest in 2000, when no long term garden was expected to take root.
The term bewildering has been used as a synonym for guerrilla gardening by Australian gardener Bob Crombie.
One high-profile example of guerrilla gardening took place in May 1996, when about 500 activists affiliated with The Land is Ours, including the journalist George Monbiot, occupied 13 acres of derelict land belonging to the Guinness company on the banks of the River Thames in Wandsworth, South London. Their action aimed to highlight what they described as "the appalling misuse of urban land, the lack of provision of affordable housing and the deterioration of the urban environment."
Have på en nat
Later, on 1 July 1996, Have på en nat ("Garden in a night") was made by the Danish Økologiske Igangsættere ("Organic starters").
May Day 2000
On May Day 2000, Reclaim the Streets organised a mass guerrilla gardening action in Parliament Square, London. After a carnivalesque procession with a samba band and a Critical Mass bike ride from Hyde Park, thousands of guerrilla gardeners occupied the square and planted vegetables and flowers. A maypole was erected, around which many of the gardeners danced. Banners hung in the square reading "Resistance is Fertile" (a pun on futile), "Let London Sprout", "Capitalism is Pants", and "The Earth is a Common Treasury for All", the latter being a quote from the seventeenth-century Digger Gerrard Winstanley. An Indymedia public access terminal was set up in the new allotment, and the statue of Winston Churchill was given a green turf mohican. The perpetrator (an ex-British soldier) was fined for his vandalism of the Churchill statue.
International Sunflower Guerrilla Gardening Day 1 May
In 2007 guerrilla gardeners in Brussels, known as The Brussels Farmers , declared 1 May International Sunflower Guerrilla Gardening Day. This is a day in which guerrilla gardeners around the world plant sunflower seeds in public places within their neighborhood (in practice this event is limited to regions of the northern hemisphere where the climate and season are most appropriate). Participants in that first year included Brussels, London and Bordeaux. Every year since then the occasion has gained momentum and been promoted through the GuerrillaGardening.org network  and in 2010 more than 5000 signed up to take part. 
Leaf Street Community Garden
Leaf Street is an acre of land in Hulme, Manchester, England, that was once an urban street until turfed over by Manchester City Council. Local people, facilitated by Manchester Permaculture Group, took direct action in turning the site into a thriving community garden.
GuerrillaGardening.org was created in October 2004 by Richard Reynolds as a blog of his solo guerrilla gardening outside Perronet House, a neglected council block in London's Elephant and Castle district. At the time, his motivations were simply those of a frustrated gardener looking to beautify the neighborhood, but his website attracted the interest of fellow guerrilla gardeners in London and beyond, as well as the world's media. Reynolds's guerrilla gardening has now reached many pockets of South London, and news of his activity has inspired people around the world to get involved. He also works alongside other troops, some local and some who travel to participate. He has also guerrilla-gardened in Libya, Berlin and Montreal. Today, GuerrillaGardening.org is still his blog but also includes tips, links and thriving community boards where guerrilla gardeners from around the world are finding supportive locals. His book, On Guerrilla Gardening, which describes and discusses activity in 30 different countries, was published by Bloomsbury Publishing in the UK and USA in May 2008.“Guerrilla Gardening: A Manualfesto” by David Tracey has accounts of community garden leaders and public officials. “Guerrilla Gardening: How to Create Gorgeous Gardens for Free” by Barbara Pallenberg is a how-to on gardening that was "everything you wanted to know about gardening but were afraid to ask" .
Richmond, Virginia, birdhouses and gardens
The installation was inspired by a combination of several local developments.
Additionally, the guerrilla gardening movement has been catching on in Richmond, Virginia. In 2006, Style Weekly reported an act of guerrilla gardening in an alley off Hanover Avenue adjacent to the new birdhouses. Also, a group called Tricycle Gardens has begun the reclamation of blighted urban spaces in some of Richmond's poorest neighborhoods. Their efforts are bringing locally grown food and a better understanding of the interconnectedness humans have with nature to the city.
Kew Bridge Eco Village, London, England
In July 2009 land rights activists moved on to a derelict piece of land near Kew Gardens in West London. Kew Bridge Eco Village is a small community of squatters who have grown vegetables and built basic wooden dwellings on the land.
Guerrilla gardening in Australia
Guerrilla gardening is prominent in Melbourne where most of the inner northern suburbs have community vegetable gardens; land adjoining rail lines has undergone regeneration of the native vegetation, including nature strips. There are a few minor disputes between guerrilla gardeners in Melbourne, with most falling into one of two groups: those concerned most with native planting and those concerned most with communal food growing. However, people with differing opinions still work together without dispute.
Guerrilla gardening in practice
Guerrilla gardeners are a diverse group of people who have different goals, values and methods of gardening on public land.
Some individuals and small groups have marijuana gardens hidden in national forests and blended in with cornfields. There are many marijuana-growing websites that give tips and experiences regarding how to secure your cannabis guerrilla garden from law enforcement and rogue harvesters. Internet forums are the primary source of information because they offer the participants a way to discuss their practice with anonymity. They are primarily concerned about keeping their plots hidden and not leaving trails. People engage in this type of guerrilla gardening for personal gain instead of for any political, environmental or beautification reasons. Because of the economic incentives, hidden cannabis crops are not usually associated with self-proclaimed guerrilla gardeners although their tactics are similar in many ways.
Many freegans (people who reclaim food from waste bins) and urban foragers who wish to live independently from the agricultural-industrial complex have also adopted guerrilla gardening. Urban populations are completely dependent on fossil fuels to import food supplies from anywhere in the world. The average supermarket food item travels 1494 miles to reach its destination . Food made up 231.9 million tons of municipal solid waste in 2000, which amounts to everybody throwing away 4.5 pounds of food a day each day of the year. Guerrilla gardening alongside with practices of urban foraging and freeganism is a way to become more sustainable and self reliant. Most freegans realize that dumpster subsidence is a way to escape monetary participation of the industrial food web but it does not offer enough to create a healthy and sustainable food system. In the event energy costs will be so high that stores will cease the ability to import refrigerated food, freegans are expanding and diversifying their practices to include much more guerrilla gardening.
Toxicity risks of guerrilla gardening
There are some health risks to foraging or planting edible plants near toxic waste sites and roads with heavy traffic due to chemical runoff that gets absorbed by the roots. Toxic plants tend to grow on toxic land. Some scientistsTemplate:Who have learned that certain types of plants absorb toxins from the soil without dying and can thus be used as a mechanism to reduce chemical ground pollution. Guerrilla gardening could be used as a way to take independent action to clean up ones community but eating a toxin-absorbent plant will deposit those toxins in the body. Urban foragers face similar health risks in this manner. Care should be taken to not eat plants that grow in areas where there is known chemical contamination or water pollution. Plants that grow on the side of high-traffic roads should also not be eaten because of automobile fluid runoff.
- Common land
- Communal garden
- Community gardening
- Community Supported Agriculture
- The Diggers
- Fallen Fruit
- Food security
- Intercultural Garden
- Seed ball
- Seed Bomb
- Johnny Appleseed
- The Man Who Planted Trees
- Urban gardening
- Urban horticulture
- Guerrilla Gardeners, a reality TV show
- Gruenewelle.org- Multilingual Guerrilla Gardening Site
- GuerrillaGardening.org- The global forum for guerrilla gardeners
- Blind Guerrilla Gardener An inspirational short film about a blind guerrilla gardener in London
- Police vs guerrilla gardeners The Guardian filmed guerrilla gardeners in London encounter the police.
- Allotmenteering Reflections on Guerrilla Gardening and Allotmenteering
- Moss Graffiti How to make moss graffiti
- Domestic Seed Bomb production Richard Reynolds demonstrates the Californian method of seed bomb making.
- Interview with the author of Urban Homestead- Erik Knutzen discusses guerrilla gardening and other collective action.
- Saving the World with Che, Mao, and Carrots - Review of On Guerrilla Gardening by Richard Reynolds for The Atlantic
- socalguerrillagardening.org 20+ years of Guerrilla Gardening in Southern California.
- laguerrillagardening.org Guerrilla Gardening in Hollywood and Los Angeles, California
- Posterchild Guerrilla Gardening by Posterchild in Toronto
- Toronto Guerrilla Gardening - Organized by the Toronto Public Space Committee
- Gruenewelle.org- Guerrilla gardening in Berlin, Germany
- Green Guerillas Supporting community gardening in New York
- London Guerrilla Gardening Guerrilla Gardening in across London, UK
- Rébellion jardinière green activists based in France
- Guerrilla Gardening Belgium Guerrilla Gardening Belgium
- Windsor Guerrilla Gardening Collective Windsor Ontario Canada
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