When was the plum blossom in this ancient poem? What is its spirit?

Plum blossoms bloom in winter, which is seen from Cold Ling Flowers Alone.

Plum blossom is a five-character quatrain written by Wang Anshi, a poet in the Northern Song Dynasty. In poetry, the power and noble character of plum blossoms are used to express those people who, like poets, can adhere to ethics and morality, advocate justice, and are not afraid of crowding out and hitting the country's prosperity in a difficult and harsh environment.