At its first weekend, about 20,000 people visited the expo each day, where they admired more than 20,000 exhibits, including 1,000 types of new flowers.

Shi Mingfang, chairman of Bright Dairy and Food, says the group built its largest flower factory in Shanghai, a 76,000-square-meter smart greenhouse to store flowers for the expo.

Song Limin, the person in charge of the Henan provincial exhibition at Fuxing Pavilion, says they have brought in 500 bonsai and floral arrangements to compete for the gold medal at the expo's flower contest.

"We started to prepare the seeds last year and control the temperature to make the flowers blossom during the expo," she says.

The Yunnan provincial exhibition has set up a big screen connected to the Kunming International Flora Auction Trading Center, and people can see live auction deals made every few seconds.

The 8th China Flower Trade Fair is also held alongside the expo, with three sessions taking place from May 21-29, June 5-13 and June 19-27. About 400 horticulture companies from around the country are selling various flowers, seeds, plants, seedlings and gardening tools at the fair.

Fei Xuemei, general manager of Yunnan Holy Flora, says that sales of flowers are set to increase in China due to rising income levels of Chinese people.

"Flowers are high value-added agricultural products, and the flower industry contributes to the country's revitalization of the countryside," she says.

Jiang Zehui, president of the China Flower Association, says the planting area of flowers in the country to date stands at 1.5 million hectares and generates annual sales of over 250 billion yuan ($39.2 billion) and a net export volume of $622 million, making China one of the biggest flower producers and traders in the world.

Chongming has been promoting its flower retail industry since it won the right to host the flower expo three years ago.