A worker examines a giant basket of artificial flowers and fruits in the center of Tian'anmen Square. The display was built to send "blessings to the motherland". [Photo by Wang Jing/China Daily]

Cultivating the flowers began early in the year, and design of the floral display started in April.

The florescence of the flowers is carefully controlled to ensure they can bloom during the National Day holiday.

"We must make sure that the flowers start to bloom on September 26 or 27, so that they are in their best shape three days later," Lan Hailang said.

Meanwhile, the artificial flowers, which weigh at least 200 kg, are fixed on top of the basket to make sure they don't fall off.

The design for the giant basket as well as the 10 floral display structures was selected from four contenders shown by the company to the Beijing municipal government, Shang said.

Li Haibo said the theme for the flower display changes each year to represent major national events, such as the Olympic Games, completion of the Three Gorges Dam project, or the launch of Shenzhou spacecraft.

"Every year the display has a theme related to politics, which means there is a big role for us to play," he said.

However, it has become more difficult for them to match their designs to reality due to the limited time available, he said.

The time given to the company is limited to 10 days each year. It also has to carry out most of the work at night because of the large number of tourists visiting Tian'anmen Square in the day and a ban on cargo trucks in downtown areas.

Shang said: "We are trying to reduce the work in the square as much as possible and get most of it done elsewhere.

"We also have to have a plan B in case rain delays construction."

Work on the flower bed and structure is only the first step, with the more important task being maintenance, which involves watering the flowers, pest prevention and maintaining the LED lights, Shang said.

The flowers are also chosen to withstand windy and rainy weather, which can affect Beijing in the autumn.

Meanwhile, work safety is the top priority, Shang said.

The company hires the best welders in the capital to ensure the steel structure is built safely. It also maintains a team of security guards to patrol the area.

Despite all this work, Lan Hailang, the engineer, said it merits all his efforts.

"The work is about facing up to challenges and living up to the expectations of the people. We will do our best," he said.