A farmer recently became very popular on the internet for his Chinese calligraphy on watermelons.

Gu Xinliang, 56, a rural teacher, has sold 3000kg of watermelons he grew on his 666 square-meter farmland within just 11 days. What is the secret key for his stunning business? It comes down to writing calligraphy.

"I didn't expect this," he told the Legal Evening News on Monday, "One day, I wrote the Chinese characters 'Fortune' and 'Longevity' on a few watermelons, and they were quickly sold!"

As many watermelon sellers flock to sell the fruit during the summer time, supply has exceeded demand. However, Gu's creative idea helped him stand out and beat the competitors as buyers loved to buy his watermellons with caligraphy both for eating and good luck.

Gu, a calligraphy lover, works on more watermelons with a greater diversity of calligraphy of blessings and good lucky phrases in Chinese, including "Chinese Dream" and "Wish you Happiness."

However, he also admits it is very hard and even causes him physical pain since he has to write the calligraphy on watermelons using his fingernails.

"Other tools may damage the watermelons. Using the fingernails to do it is the best way, but my fingers are aching now."