What is the meaning of frost leaves redder than February flowers?

Frost leaves: Maple leaves turn red after frost in late autumn.

Original text:

Travel in the mountains

Author: Du Mu

As far away as Hanshan, the stone path is oblique, and people are in Bai Yunsheng.

Stop and sit in the maple forest late, and the frost leaves are red in February flowers.

Author: Du Mu (803-853), a poet in the Tang Dynasty. Mu Zhi was born in Jingzhao Wannian (now Xi, Shaanxi), and his grandfather Du You was a famous prime minister and scholar in the middle Tang Dynasty. In 828 A.D. (the second year of Daiwa), he won a scholar and was awarded the title of library librarian. He worked as a staff member in other places for many years, then as a censor, a secretariat of Huangzhou, a secretariat of Chizhou and a secretariat of Zhou Mu, and later as a foreign minister of Sixun. I think I have the talent to help the world. Most of these poems quote Chen's works. A lyric poem about the scenery is so beautiful and vivid. Known for its seven-character quatrains, it has a particularly broad realm and a particularly deep sense of history. For example, Chibi, Tiaojiang Pavilion, Huaqing Palace, Bo Qinhuai, Tomb-Sweeping Day, Jiangnanchun Jueju and Xing Shan. They are all masterpieces that have been handed down to this day. People call it Xiao Du, and Li Shangyin is collectively called Du Xiaoli, which is different from Li Bai and Du Fu. There are twenty volumes in the Collected Works of Fan Chuan handed down from ancient times, and eight volumes of his poems are included in The Complete Poems of Tang Dynasty.