"In the Botanical Garden, weak ginkgo trees turns yellow from mid-November, while stronger trees wait until the start of December," Xiu said. "Some leaves fall one week after changing color."

She added, "The radiative cooling in city suburbs is higher than downtown, so the color changes there appear earlier."

Not all red-colored trees reflect autumn foliage. "Some trees are red all year around, such as cherry plums and purple-leaf sand berries," she said.

Facts about autumn foliage

Ginkgo 銀杏

Scientific name: Ginkgo biloba

For many people in Shanghai, the ginkgo is the iconic symbol of the autumn season.

A species native to China, the ginkgo is widely grown in parks and along sidewalks. The trees grow very slowly with a long life expectancy. They don't bear nuts until 20 years after planting.

Ginkgo leaves are fan-shaped and turn golden yellow in autumn.

The ginkgo nut is also known as bai guo, or "white fruit." It's a traditional Chinese ingredient in many desserts and congee. Although the nut is believed to have health benefits, it can be poisonous if eaten raw or in excess.

Wingleaf soapberry 無患子

Scientific name: Sapindus saponaria

The bright yellow foliage of wingleaf soapberry is also a star of the season.

The small to medium-sized deciduous tree's root and nuts are believed to have medicinal properties, and the peel containing saponin can be used as soap.

The wingleaf soapberry is commonly found in eastern, southern and southwestern China.

Chinese firethorn 火棘

Scientific name: Pyracantha fortuneana

Also called graberi, this tree is an evergreen shrub in the rosaceae family. It produces abundant red berries that will last through the winter.

Each spike can grow 10 to 20 small berries that turn red beginning at the end of September. Birds love the berries.

Dawn redwood 水杉

Scientific name: Metasequoia glyptostroboides

The autumn foliage of the dawn redwood is a foxy reddish-brown. It's among the last trees to display autumn foliage, usually occurring in late December.

Native to the region border on Chongqing City, and Hubei and Hunan provinces, the dawn redwood was once considered extinct. Then, in the late 1940s, a 400-year-old tree was found in Moudaoxi on the border of Hubei and Sichuan provinces.

Since then, the tree has been protected and is widely cultivated across China and around the world.

Japanese Zelkova 櫸樹

Scientific name: Zelkova serrata

A flowering, slow-growing plant native to East Asia, the Japanese zelkova is widespread in China, where it's grown as an ornamental tree. It can grow as tall as 30 meters. The autumn foliage is yellow, orange and red.

The wood of the Japanese zelkova is often used for furniture and in making taiko drums.