The site in Tse Uk Tsuen, off Kam Sheung Road, has since been given over to a market garden, rows planted with organic vegetables from eggplants and pea shoots to beetroot. Besides running a Sunday market to sell produce and home-made condiments, Sangwoodgoon, meaning "life repository" in Cantonese, also organises talks and movie screenings (a month-long film festival on sustainable agriculture around the world ends this weekend).

Jenny Li Chun-nei, a photographer and co-founder, explains their decision to live off the land.

"Just like people feel a deep sense of loss after the umbrella movement drew to a close, we didn't want our group to just disband and go back to our former life after the Choi Yuen Tseun incident. So we extended it here and continue our campaigns to prompt society to think about issues such as self-sufficiency and sustainable living."

It was something of a leap of faith for the founders, none of whom had real farming experience. "Four years ago, we thought it was impossible to live on a farm and produce our own food. Hong Kong, being a consumerist society, couldn't possibly provide the conditions for us to do that. If we gave up our jobs, could we fend for ourselves? But we still wanted to give it a try," Li says.

From transforming a barren piece of land into a market garden, installing drainage and electrical wiring to constructing latrines, they learned to do it all - with guidance from farm veterans and Choi Yuen Tsuen residents.

"Each of us had a lot of education. But when we got back to basic living, we found we couldn't solve a lot of practical problems," Li says.

After much trial and error, however, Sangwoodgoon is now finally producing enough to give small salaries to the five people working full time on the experimental farm.

"In the past, our yield was paltry and irregular. I could only pay them a travel subsidy every three months then," says Li, who handles the farm's finances. "While we still go out to buy meat to make soup, we plant our own rice so we can attain a high degree of self-sufficiency."

Their fields now yield about 4,000 catties of farm produce, including rice and vegetables, each year. Deducting what they consume themselves and the HK$4,000 annual rent for the site, sales of farm produce can now generate monthly incomes of a few thousand dollars to each member of the collective.

But to succeed they had to gain the trust of nearby villagers for their experiment, says Sangwoodgoon co-founder and part-time cultural studies lecturer Chow Sze-chung, not least because these were the people who would buy most of the produce.

"When we first came here, we were strangers and the villagers had been living here for ages … Now, our customers are all nearby residents."

However, he adds: "The farmers still think we are here only temporarily and are only playing [at farming]. It takes time [to change their mind]."

Over the past year a couple of new members have joined the collective, including Tse Uen-man, who hopes to run her own farm eventually. The 23-year-old quit an associate degree course on philosophy at Lingnan University last year to gain farm experience working at Sangwoodgoon. She receives just HK$2,000 a month for her labours and must supplement her earnings by giving tuition to schoolchildren. But Tse has no regrets.

"My friends are all studying or working in office jobs. While it might seem an unconventional career choice in Hong Kong, I enjoy the lifestyle of being a farmer. I used to feel stressed when I was studying. After coming here, my health has improved. My parents support my decision although they worry farming will be too tough [physically] for a slight girl like me."

James Lam Chi-lap also has his parents' backing for turning his back on a teaching career to join the collective while his friends became doctors, lawyers or went into banking.

Although he studied art history in Scotland, Lam grew increasingly preoccupied with sustainability issues after graduating and quit his job a year ago to join Sangwoodgoon.

"My dad is a professor in finance. He's always worried about future scarcity of resources. He thinks that although conflicts and wars over resources won't happen in my generation, they will erupt in his grandchildren's generation. So he understands why I need to do what I am doing," he says.

But in this pursuit Lam is determined to be self-reliant, even if it means working several jobs: "If I need to rely on my family financially, that would be meaningless."

He makes a little extra income by taking on design commissions and leading study trips for students from the secondary school where he used to teach. While such tours usually involve language immersion in Western countries or excursions to learn more about China, Lam is organising a visit to Niigata, Japan, to learn about its farming system and join the Echigo-Tsumari art triennale.

Lam says the Niigata experience shows how cultural activity can inject new life into a fading farm community.

The modern art festival was initiated in 2000 by a Tokyo gallery owner to revitalise his hometown in the Echigo-Tsumari region, where young people were increasingly leaving to work in big cities. His team persuaded farm owners and community leaders to work with artists to install sculptures and other artworks around their fields, vacant houses, closed schools and playgrounds. It has since grown into an international event attracting large numbers of visitors.

Lam hopes such exposure will change children's thinking about nature. Recalling a school project to grow potatoes during his teaching days, he says the first thing students asked was for a pair of gloves.

"[Most children] think soil is something dirty. Parents even swipe their kids' hands with antiseptic towels after they touch a plant. Many children in cities grow up thinking nature is something to avoid. I want students to understand that humans are a part of nature and there's nothing to be afraid of."

The budding farmers hope to replicate the Niigata experience at Sangwoodgoon and reach out to more people through cultural activities such as movie screenings.

"This is the first time we've held the film festival and we hope to stage it annually in future," says Li, who will lead a photography workshop in the autumn, when students can take pictures of the harvest and exhibit their work.

"Ninety-nine per cent of food in Hong Kong is imported. People should think about the importance of self-sufficiency. We want to promote the importance of farming when the government and big corporations are hell-bent on grabbing land for development," Li says.

Last month the government announced proposals to buy back about 80 hectares of private farm land to create an agricultural park that aims to promote modern management and accommodate farmers displaced by development, while a fund would be set up to provide matching grants to develop hi-tech farm methods.

But to Chow, the plans, which are estimated to cost HK$7 billion, fail to deal with the problems afflicting local farmers.

"If only hi-tech agriculture ventures can set up in the park, farmers using traditional methods cannot benefit at all. And there's concern over using public money to help well-endowed business groups develop advanced farming such as hydroponics," he says.

"The government should find out what is wrong with agriculture. They should address issues such as how local agricultural production relates to food security."

Even as it seems to boost agriculture, Chow notes, the government has announced plans to build a new town in the area between Ng Ka Tsuen and Kam Sheung Road MTR station. "Land value in the surrounding area will shoot up, which will put pressure on our farming venture. Our site might even be taken away for development.

"Why should Hong Kong rely so heavily on food imports?" Local produce accounts for less than 2 per cent of the city's food consumption, yet great stretches of agricultural land are left vacant by developers or indigenous residents awaiting compensation once the land is converted for commercial or residential use.

"Like other farmers in the New Territories, I feel insecure because after years of effort, the land can be taken away for development. I'm afraid that the whole of the New Territories will be urbanised in future."