Why does Lao She's poem "Shouyan Cherry Blossom Qiu Yan Maple, Early Summer Blue, Deep Red" begin with "Shouyan" instead of "Chun Yan"?

Because cherry blossoms are really a flash in the pan among flowers. Because their flowering period is very short and gorgeous, people will especially like the cherry blossoms they see every year. Cherry blossoms last only seven days from flowering to withering, but they bring people endless thoughts ... Shouyan Cherry Blossom is a maple tree in Qiu Yan, which is bright green and crimson in early summer. I think the author feels the magnificence of cherry blossoms, but also feels sorry for its short life journey.