Chrysanthemum is a perennial herbaceous plant of the Asteraceae family. Its petals are tongue-shaped or tubular. It is a precious ornamental flower cultivated through long-term artificial selection, with more than 3,000 varieties. Chrysanthemum is one of the top ten famous flowers in China and has a cultivation history of more than 3,000 years in China. Chinese people love chrysanthemums. Since the Song Dynasty, there has been an annual chrysanthemum festival among the people. Many poets and painters of all dynasties have used chrysanthemums as the theme of poetry and painting. Therefore, a large number of literary works and cultivation experiences praising chrysanthemums in all dynasties have left many famous works for people. Zhaojia Garden has a long history of flower cultivation. According to the "Pengpu Township Chronicles", "Zhaojia Garden in the southern border is also the production base of flowers and trees in Pengpu. It was first planted by Zhao Dejia during the Qianlong period of the Qing Dynasty. Later, his descendants multiplied and all made horticultural flowers as their business, built flower sheds, and continued to grow all year round. The countryside called it "Zhaojia Garden." Chrysanthemum is one of the highly hybrid varieties, and the original species is produced in China. Through the continuous practice and summary of generations of gardeners in Zhaojia Garden, the history of only autumn chrysanthemums has been rewritten into the production and supply of chrysanthemum cut flowers in all seasons. According to the quality of chrysanthemums and the natural flowering period combined with artificial control, the flowering period is divided into spring chrysanthemums (around Qingming Festival, also called four-season chrysanthemums and May Day chrysanthemums), summer chrysanthemums (Guangzhou yellow, dragon head yellow, small white, big head white), autumn chrysanthemums (early blooming chrysanthemums in October and late blooming chrysanthemums in November, quality chrysanthemums, cut chrysanthemums), and winter chrysanthemums (flat-headed yellow, flat-headed white, delayed flowering under light). The garden has fresh flowers for sale all year round. From 1987 to 1991, the Shanghai Municipal Science and Technology Committee commissioned the Municipal Flower and Tree Company and Shanghai Agricultural College to successfully carry out the selection and cultivation of a series of cut chrysanthemum varieties in Hutai Flower Garden. In 1989, 325 varieties of chrysanthemums were cultivated, making the flowers in Zhaojia Garden more famous.