A bitterly cold Sunday morning in winter possibly wasn't the best time to visit an organic farm in northern China. But there was still plenty to see and a lot to learn at God's Grace Garden - located about an hour's drive south-west of the capital, Beijing.

The 150mu farm - or about 10 hectares - is top to toe organic, and not an inch of useable land is wasted.

Established in 2001 by Terese Zhang Zhimin--God's Grace Garden is now considered a model of organic farming - and sets the standard for others to follow.

Freelance writer on organic food and natural living, Yinghui Zhang-Carraro, is enthusiastic about the work being done at God's Grace Garden, and says it could provide a platform for others to learn about organic farming.

"Farmers and students can be trained and learn a lot about real organic farming, and how a farm like this can be self-sustaining."

Most conventional farms are monoculture - devoted to just one or perhaps two crops. But studies have shown this depletes the land's long-term ability to sustain agriculture.

Terese Zhang says as the land on conventional farms becomes less able to sustain crops, farmers turn increasingly to chemical fertilizer and pesticides.

"Simple rotation will ultimately destroy the land,"" she said.

In the beginning (of industrial scale farming), she said, farmers would only use between two to three kilograms of chemical fertilizer per mu of land.

"But now some farmers are using up to 50 kilos of chemical fertilizer. Who knows what will happen when they use even more? Perhaps they will even have to stop farming to allow the land to recover."

According to a recent report by the environmental group Greenpeace, organic farming offers a practical way to restore land that has been degraded by chemical fertilizers and monoculture farming.

Their report said "organic farming supports greater biodiversity in the environment, conserves soil fertility and stability, and does not pose any risk of water pollution from pesticides.""

Terese, says the answer to most agricultural questions - including pest control - can be found by listening to nature, not just the scientists.

"The pests they are just the messengers sent by nature. We just need to read the message from nature and understand it. Then we can have better farming practices."