A unique orange brand has become one of the most coveted fruits in China this winter, though it is sold for five times the average market price -- and is invariably out of stock.

"It's not just because the fruits are exceptionally sweet and juicy," said Shi Jin, an office worker in Shijiazhuang, capital of north China's Hebei province. "The brand has a big story behind it."

For weeks, Shi has been trying to buy the legendary "Chu's orange" from its online retailer, Benlai.com. The fruits, however, are always in short supply, though they are sold for at least 25 yuan a kg, compared with an average 5 yuan per kilo for ordinary oranges.

"Even when there are oranges in stock, the online store only takes orders from Beijing and Tianjin," according to Shi.

The "Chu's orange" is named after 85-year-old Chu Shijian, China's former "tobacco king" who built a struggling tobacco firm into the country's largest and most profitable cigarette producer in the 1980s. Chu, however, was jailed for life on corruption charges in 1998.

After he was released on medical parole in 2002, Chu contracted 160 hectares of wasteland in the mountains of southwest China's Yunnan province to plant oranges.

Today, his fruit farm produces 8,000 tonnes of oranges a year, generating 30 million yuan in annual profits. Most of his products are sold online.

"These are not ordinary oranges. Each fruit carries Chu's story of perseverance," said Shi. "So the fruits are not just delicious, but inspiring, too."

Indeed, many buyers said they coveted Chu's oranges because they respected and supported the old man.