Guerrilla Gardening

Picture a garden. Step into it. Stroll around. What do you see? Perhaps a riot of tumbling terraces, topiary and pergolas, a cheerful blast of a blooming border or an explosive vegetable patch. Or maybe you are just reminded of a muddy lawn and cracked concrete patio. Whatever you are imagining, it is likely that to one side of it stands a house.

You are picturing a garden as most people see one - as an extension of a home, a landscaped setting to live in, a private space cultivated for the primary pleasure of the permanent occupant. While generous owners allow guests to share their garden, ultimately it is theirs and not yours. If you want to be a gardener, then you must do so in your own garden or else obtain permission to garden someone else's land.

But some people have a different definition of gardening. I am one of them. I do not wait for permission to become a gardener but dig wherever I see horticultural potential. I do not just tend existing gardens but create them from neglected space. I, and thousands of people like me, step out from home to garden land we do not own. We see opportunities all around us. Vacant lots flourish as urban oases, roadside verges dazzle with flowers and crops are harvested from land that was assumed to be fruitless. The attacks are happening all around us and on every scale - from surreptitious solo missions to spectacular campaigns by organised and politically charged cells.

This is guerrilla gardening.

It was 2am one October night in 2004 when I stepped outside the law. I had recently moved into a 1970s tower block on a bleak roundabout in Elephant & Castle - an area of south London notorious for its labyrinth of pedestrian underpasses, garish pink shopping centre and traffic volumes to rival Britain's busiest motorways. It is the kind of environment that drives people to crime. My crime was gardening on public land without permission and battling whatever was in the way.

The split-level flowerbeds beneath Perronet House were a grim tangle of old shrubs, builders' debris and litter. Even weeds seemed unwelcome in the barren bed next to the tower's front door. Happiest were an old white butterfly bush, rampant ivy and periwinkle, but this axis of evil had thuggishly taken over what the architect had presumably imagined as splendid interlocking beds cascading down from the entrance to the parade of busy bus stops below. An official gardener should have been taking care of the beds, but all I could see flourishing was litter. Rather than wait for the council to sort them out, I decided to do it myself.

So down I went in the early hours, my body charged with tea, to pull out weeds, dig in manure and plant red cyclamen, lavender and three spiky cabbage palms. I felt like some kind of mischievous tooth fairy or green-fingered vandal. I hoped that by gardening at such a strange time I would avoid trouble with neighbours and the council, both of whom, I feared, would be irritated by a meddling newcomer. That first night I improved the patch by the main entrance, but there was a lot more gardening to be done and the plants had years of growth ahead of them.

The plants survived the next few uncertain days and I picked up a little gossip that the improvement had been noticed by residents. Most assumed the council had finally got round to doing something. I was not yet confident enough to out myself to the neighbours. I preferred to remain undercover and continue my gardening uninterrupted.

Yet it was all too much fun to keep secret. I was happily entertaining friends with my exploits, and chose to spread the word further by blogging about it. I did not give much thought to the name when I set up the site, but GuerrillaGardening.org seemed to sum it up, and for a while I even thought I had invented the term. Weeks later, as I surfed around to see how my site was performing in search engines, I was amazed to discover all sorts of references to guerrilla gardening. There were guerrillas all over the place! As they shared their stories with me, I realised that I was part of something much bigger.

I'll identify the guerrillas here by the "troop numbers" they were given when they signed up at GuerrillaGardening.org. Surnames have been omitted because some guerrilla gardeners prefer to remain anonymous.

Ava 949, from San Diego, told me how she had "seed-bombed" a 10-mile (16km) stretch of Imperial Avenue by lobbing fertile projectiles from her car window. Lucy 579, a London artist and self-proclaimed "fairy spreading magic dust", targets waste ground near Hither Green railway station, scattering wildflower seeds with abandon. She describes her station now as "Dog Daisy Heaven", a place where she can pick a flower for her hair in the morning before the commuter crush.

Thomas 347, from Davenport in Delaware County, has lined the road that passes through his town with daylilies. In Crewkerne, Somerset, Ben 2676 grew maize in a shabby planter right outside the entrance of his local supermarket, with the help of his young daughters Lily 2677 and Noor 2678.

Driving through Hampshire, Stephen 1337 noticed a neglected roundabout by Minley Wood, near where the body of murdered teenager Milly Dowler was found in 2002. He wanted to cheer the place up, so he planted daffodils.

In New York, Peter 509 filled the median planter that runs down Houston Street with more daffodils to give drivers waiting at the junction something pleasant to look at. The bulbs had been donated by Hans van Waardenburg, a Dutch supplier who pledged to give New York half a million bulbs every year to commemorate 9/11. Still without permission, Peter also built planters around trees along Houston Street, painting them bright blue with white clouds on. His grand dream is of a long roadside garden - a twisting ribbon that weaves together the green pockets of New York's gardens.

It was in the Big Apple that the term "guerrilla gardening" was coined in 1973, by a young painter called Liz Christy. Liz noticed tomato plants growing in the mounds of trash that littered derelict lots in her neighbourhood. The plants had clearly sprouted from fruit in the discarded rubbish, and their germination promised potential in the landscape. Likewise local children were finding places to play in the urban wastelands. Taking inspiration from what they saw, Liz and her friends scattered their own seeds in vacant lots, before deciding to create a community garden. Thirty-five years on, the garden she and her friends made on the corner of Bowery and Houston streets holds a grove of weeping birch, flowering perennials, vegetables and a grape arbour. A family of turtles swims in a large pool, and the hive is full of bees.

Guerrilla gardeners do not restrict their horticultural aspirations to the ground, however. When Helen 1106 walks around London she looks up and imagines a romantic alternative metropolis, a landscape of towering buildings covered with vegetation rather than glass and steel. She has begun her mission by planting ivy in nooks and crannies near the Bank of England. A few miles to the north, Sean 2350, despite being blind, has trained climbers up the telegraph pole and along the cable outside his house in Kentish Town.

One excellent reason for cultivating someone else's land without permission is hunger. Mama Afuwa 3187 lives near Kagoma, Uganda, and rents a small bungalow. She has no land, but when Lyla 1046, from London, visited her she was shown a fine crop of onions planted on the common scrub beside her home. Elsewhere in Uganda, Lyla came across land set aside for road expansion that had been illegally planted with maize, and unemployed residents growing plantains in what was once one of the largest industrial estates in East Africa.

My own guerrilla activity has moved beyond Perronet House, with the help of friends and family such as Joe 004, Clara 005 and My Mother 008. Joe and Clara had no experience of gardening, but when the subject was raised at the end of a boozy dinner, they immediately joined me in planting herbs on a traffic island. This was no drunken one-night stand, as three years later they are still among the regular troops.

A typical project was a neglected roundabout in the shadow of the 300-year-old limestone obelisk on St George's Circus, Southwark. Two years ago, its elliptical bed contained just two shaggy cabbage palms and a desert of compacted soil and litter. Now, with the help of many volunteers, it has become a thriving herb garden and shrubbery. Two spiky New Zealand flax squat at either end of a swath of small azaleas, Michaelmas daisies, heathers of various shades, pittosporum, a bed of lavender and rosemary underplanted with tulips and a Christmas tree.

Guerrilla gardening can, of course, put you in conflict with the landowner and those who are employed to enforce rules. While trespass is only an issue if the land is private, gardening anywhere without permission can be treated as criminal damage. Potentially you are creating obstruction, defacement, pollution and disorder, even though that is not the intention of most guerrilla gardeners.

In Reading's shabby Katesgrove district, just off the deep-cut dual carriageway of the Inner Distribution Road, Stuart 1952, a painter and decorator, led a team of guerrilla gardeners in creating the Common Ground Community Garden on some neglected waste ground. They cleared a large area of needles, used condoms and broken glass and replaced it with a small lawn, wood chippings, seats hewn from logs and pots of purple petunias.

Stuart reached out very publicly to the community, inviting them to enjoy the reclaimed space with an inaugural barbecue. This, however, alerted Reading borough council, which obtained an injunction on the grounds of "health and safety", an excruciating claim given the state the land was in before. The barbecue carried on regardless, 200 people came, and the guerrillas set about fighting a legal battle for the right to continue. The garden was still looking splendid when I visited in August 2007, but Stuart and his team continue to face legal challenges.

I have had several encounters with the authorities. The most frustrating was with a street cleaner in Southwark, over "my" use of "his" rubbish bins. When he saw me putting litter from some nearby flowerbeds into the bins (together with some garden waste) he challenged me: "You're filling them up too quickly." I tried to reassure him that in our own way we were doing the same job, but he seemed unsatisfied. The next morning I found the entire contents of one bin emptied over my freshly sown seedbed. The situation was resolved when the local newspaper picked up the story. "Guerrilla gardener goes ape," screamed the headline. Since then Southwark council seems to have been shamed into accepting my free rubbish collection.

Some guerrillas find they become invisible to busybodies simply by putting on a high-visibility jacket. However, a word of caution. I tried this approach late one night while cutting a new bed for nasturtiums in the tatty turf that covers the north roundabout in London's Elephant & Castle. By coincidence, many other men in fluorescent jackets were also in the area that evening, busy renovating the nearby underground station. In theory my jacket and I should have blended into the Day-Glo blur, but I could not have been more conspicuous. While they were all wearing orange jackets, mine was yellow. A gang of four soon came over, curious to see what I was up to. I explained I was just gardening but they observantly inquired, "Why is there a bus company's name across the back of your jacket?" If you are going to assume a disguise, do your research.

Surprisingly, perhaps, I have had little trouble with police and security guards. One uniformed duo arrived with lights flashing and siren blaring - called out on suspicion that I was stealing plants - but I showed the officers that my tub was full of dandelions. Luckily for me, they recognised weeds and, looking puzzled (I was gardening alone at 12.30am), let me continue.

My most serious problem with the police was while driving to a dig. They pulled me over under the Prevention of Terrorism Act, suspecting my car was laden with high-explosive fertiliser (it could have been, but that day it was woodchip mulch). More recently, passing police have recognised us as guerrilla gardeners and quite happily shared a cup of tea and supported what we were doing (though they have not yet dug alongside us). Generally they have more serious disturbances to deal with.

And, on the whole, public opinion is increasingly on the guerrilla gardeners' side. Well-wishers have sent me cheques with instructions to take volunteers out for a slap-up meal. While I was digging on a traffic island near Blackfriars Bridge in London, a security guard called Sikander came over from a nearby office and took requests for fresh fruit juice and bananas. And I have had drivers spot me, pull over to the kerb and thrust money into my muddy gloves when they realised what I was doing. The first time this happened there was a moment of ambiguity about what service was expected from me, but there was no negotiation - they expected nothing but to drive past flowers.

What to plant?

A guerrilla gardener should consider applying elements of "shock and awe" to planting. There are three key horticultural tactics you can deploy for maximum impact:

Colour

· Daffodils (Narcissus eg 'Jetfire' or 'Vulcan') and tulips (Tulipa eg 'Emperor' or 'Kingsblood') should be planted in autumn. By spring they will have become a legion of bright trumpets marching 15cm (6in) high, and they will return year after year.

· Canna lilies (Canna eg 'Tropicana' or 'Bengal Tiger') have brightly coloured flowers and striking, paddle-shaped, tropical-looking leaves. The canna is a herbaceous perennial and is available with flowers in all sorts of shades of red, pink, yellow and orange. It is also known as 'Indian Shot' because its tiny hard seeds make good bullets.

· Primroses (Primula eg 'Wanda Supreme Series') are herbaceous perennials that form neat spots of colour, with bell-shaped flowers of assorted blinding colours that pop up from a base of ground-hugging broad leaves. They flower from winter to mid-spring.
Incongruity

· Sunflowers (Helianthus annuus) radiate their yellow sunshine from stalks up to 5m (16ft) high. Although they prefer moist ground, you can grow them up to about 2m (6ft 6in) high in dry soil (and you can eat the seeds). They help break up compacted soil and also extract lead from the ground, but avoid eating the flowers if you are using them to clean land in this way.

· Christmas trees (Picea abies) are common additions to urban centres for a couple of months, but only as depressing dying specimens. Grow one that the community can enjoy throughout the year. If you have room, go for a 40m (130ft) beauty. Otherwise try a dwarf cultivar such as 'Gregoryana'.

· Coastal redwood (Sequoia sempervirens) or giant redwood (Sequoiadendron giganteum) are the tallest trees in the world. They are tolerant of winds and pollution and can live for thousands of years. Unfortunately, they will only tower over insect life while we are alive, but why let time hold you back from aiming high?

Fragrance

· Lavender (Lavandula angustifolia) has fragrant leaves all year round and sweet-smelling flowers during the summer. It is also tolerant of fairly poor, dry soil and attracts bumblebees.

· Common sage (Salvia officinalis) is an evergreen perennial that bears fragrant hairy leaves of up to 8cm (3in) long all year round. Available in a variety of flower colours, and edible too, it enjoys full sunshine.

· Mock orange (Philadelphus coronarius) is a deciduous shrub, 3m (10ft) tall with very fragrant, white cup-shaped flowers in early summer. It is native on scrubland and rocky hillsides around the world, so will survive in a fairly poor, previously neglected environment, and it loves alkaline soil.

What is a seedbomb?

Scattering seeds is the easiest way to guerrilla garden. It is gardening in an instant, free from tools. Some plants will perish, some will flourish. You do not even need to stop moving to do it - Tony 830 releases handfuls of Welsh poppy (Meconopsis cambrica) seeds while driving along the M60 near Barton Bridge, Lancashire. These yellow poppies will grow in both damp and dry conditions and are virulent self-seeders, ideal for carpet-bombing in this way.

Seeds must have soil and water to germinate, however, so they need to land in favourable conditions. If you are trying to turn a mountain of rubble and litter into something a bit more beautiful, just throwing seeds is not enough. Using seed bombs is the smart approach; these include soil and water to help the seed get off to a good start, and are packaged like grenades so that they can be more easily fired into otherwise inaccessible places.

Kathryn 079, a professor of art in California, has been seedbombing since 1991 with avocado-shaped projectiles made by mixing and pressing together compost, native plant seeds and dextrin (a corn-starch derivative used as a binder in candy bars and cattle feed). Her inspiration came during a drought in Santa Barbara, when she saw the once beautiful landscape looking dead.

Ella 1305 and Aimee 1306 have constructed an elaborate biodegradable device - a kind of seed shell - by sucking out the contents of a chicken's egg, pouring in wildflower seeds and a little compost and writing a message of hope on the outside.

More powerful forms of seedbombing have been developed. Christopher 1594 in Richmond, Virginia, creates "seed guns" by moulding red clay, organic compost, water and an assortment of seeds into the shape of 9mm pistols. A Danish collective developed the N55 Rocket System - a large weapon fuelled by a mixture of polyethylene and laughing gas that can be towed on the back of a bicycle.

"Won't that all get pinched by the morning?" has been the reaction of sceptical passersby when they see us installing showy new plants where before there was nothing. In most cases their pessimism is unfounded, but I cannot deny that thieves and vandals are a problem when gardening in publicly accessible space. Two years in a row now, my great big red poppy (Papaver orientale) outside Perronet House has been torn from its stem almost as soon as it has bloomed. Luc 158 in Montreal, who plants a long, L-shaped bed at the foot of a pavement wall along Sherbrooke East, suffers an attack at the same time each year. Andrew 1679 had a Washington palm (Washingtonia robusta) and a Scots pine (Pinus sylvestris) stolen from a bed in Hackney. We take such thefts on the chin, as disappointing but acceptable losses in battle.

Matt 1764 and Jennifer 1765 in Fillmore Street, San Francisco, have learned to find fun in the ups and downs of their streetside guerrilla gardening. A vandal rips up their wild flowers in the tree pits and destroys their fencing, but they call their creepy pest the Grumple. They say "for every act of vandalism he does we are coming back with double the amount of love ... If you are going to do this you have to stay strong. The amount of good the flowers do far outweighs the pain caused by the Grumple." They even turn their ripped and strewn wildflowers into bouquets to take home.

Adam 276 in New York does not take it on the chin; he fights back. When one vandal peed on his flowers, he retaliated by directing his hosepipe directly into the offender's open-top BMW. Now Adam has installed a defence against urination - a piece of clear plastic sheeting that he proudly calls the "piss panel".

If you cannot face the battle head on, what you can do is make your garden less obviously showy. Dramatic, exotic plants attract attention, so if you use them try to do so where pedestrians are less likely to linger or reach over. Or plant them en masse, so that one does not stand out as a tempting beacon, and so that you can afford to lose some. Be encouraged by the words of Chance, the gardener from the Oscar-winning horticultural comedy Being There: "As long as the roots are not severed all is well. And all will be well in the garden."