The Age recently had an article on the emerging practice of "guerilla 
gardening", taking a look at the "Gardening guerillas in our midst". This 
concept seems to have steadily increased in popularity in recent years 
(admittedly from a very low base) as the permaculture movement's ideas have been 
propagated through the community.
Unlike the usual approach taken when trying to grow food in the suburbs - 
converting spare land on your own property (as discussed by aeldric previously 
and, more recently, in Jeff Vail's series on A Resilient Suburbia) - guerilla 
gardening involves cultivating any spare patch of urban land that isn't being 
used for another purpose, which could provide a substantial addition to the food 
growing potential of suburbia.
Genesis Of The Guerilla Gardeners
The idea of planting on vacant land has been around since at least 1973 when 
New Yorker Liz Christy and her "Green Guerilla" group transformed a derelict 
private lot into a garden in the Bowery Houston area of New York.
Since then the practice has spread to the US west coast, the UK and there 
have been reports of rogue gardeners in action in Brisbane, Sydney (with the 
Sydney Morning Herald calling the practitioners "bewilderers") and Melbourne. 
What Does It Involve ?
In his book "On Guerrilla Gardening", Richard Reynolds, a 30-year-old former 
advertising employee who now runs guerrillagardening.org, defines the activity 
as "the illicit cultivation of someone else's land".
"Our main enemies are neglect and scarcity of land," says Reynolds, "Land is 
a finite resource and yet areas like this are not being used. That seems crazy 
to me. And if the authorities want to get in the way of that logic, then we will 
fight them - but peacefully - through showing them what we can achieve with 
plants."
Guerilla gardening is a crime in Britain (digging up land you do not own is 
classed as committing criminal damage) but Reynolds insists it is a victimless 
crime and is clearly unfazed by encounters with police.
Practitioners plant herbs, vegetables and fruit trees in roadside nature 
strips, along railway lines and in other unused pieces of urban land. They then 
encourage the local community to tend the plots and reap the harvest.
Choosing the right sites is important for guerilla gardeners to avoid running 
foul of councils and other landowners. As one gardener noted in The Age", "It's 
got to be somewhere that no one wants to use. The whole idea is to turn 
something that was totally useless into something beautiful and useful. If you 
can find solutions like that, no one's going to hassle you."
Energy Bulletin co-founder Adam Grubb (sometimes known as Adam Fenderson) 
runs another web site called "Eat The Suburbs" and has achieved a measure of 
fame in his home town of Melbourne encouraging people to engage in "urban 
foraging".
Another person encouraging urban gardening, much to my surprise, is new 
London mayor Boris Johnson, who has launched a project called "Capital growth" 
that aims to convert 2012 London rooftops and patches of vacant land into 
vegetable gardens, with a target date of 2012. 
In a way this seems to be a revival of the English tradition of "allotments" 
- a more organised form of urban gardening from a previous age.
How much food could be grown this way ?
I haven't got the foggiest how much additional agricultural production could 
be achieved if the world's urban areas were swarmed by bands of guerilla 
gardeners, but walking around my own suburb and imagining every tree along the 
roads being a fruit or nut tree, and every little scrap of land that has been 
abandoned to weeds or scrub turned into a wild herb and vegetable patch, makes 
me think that everyone could have a much healthier diet and save a lot on their 
food bills if this was the case.
And we'd avoid a huge amount of 'food miles" (and the oil consumption this 
involves) while doing so.