Guerrilla gardening is the process of growing and cultivating plants on land which you do not legally own. The term was coined by the Green Guerrillas, a non-profit environmental group based in New York in the 1970s, who transformed a derelict site into a garden; the site is now protected as an official city park.
Although seed-bombing a neighbour’s garden is technically guerrilla gardening, the practice is most typically used for abandoned and under-cultivated community spaces, such as tree pits, roundabout centres, and building sites left in limbo. In these cases, guerrilla gardening is an example of meanwhile use. A guerrilla-cultivated space that becomes sufficiently popular and gains community support may potentially gain official recognition from local councils, but some state organisations have a concrete rather than green vision of an aesthetically-pleasing London.
An easy way to get started guerrilla gardening is to plant flowers in one of the tree pits on your street. It is important to consider the kind of plants you begin with, as seedlings can be mistaken for weeds. Richard Reynolds, a guerrilla gardener from South London, recommends using mature, flowering plants to make a significant, immediate impact. Some guerrilla gardeners work by night to avoid legal repercussions, while others work in groups during the day to generate publicity for and engagement with the movement. There are online forums where fellow guerrilla gardeners can be found, and with whom you can start a new project in your local area, or you can simply begin by yourself or with a friend.
Plants and seeds can be purchased online and in shops, as well as sometimes given away for free on sites like Freecycle. The most successful plants will be those that are hardy and native to London; perennials, wildflowers, and annuals are all good choices. For tree pits in particular, shade- and root-tolerant woodland plants are especially suitable, such as oak leaf hydrangea, azaleas, campanula, and chrysanthemums.
Care must be taken if growing fruits and vegetables, as in high-pollution areas the plant can soak up toxins through its roots and into the fruit of the plant, making it potentially dangerous to eat. However, growing plants not intended for consumption can have a positive impact on pollution levels in the area, as the plants will take in carbon dioxide in the atmosphere.
On Guerrilla Gardening: A Handbook for Gardening without Boundaries, Richard Reynolds, Bloomsbury 2009