Read "Immortelle" at The Eldritch Dark:
This poem of a remembered love features an interesting color contrast between the two stanzas. In the opening stanza, Clark Ashton Smith (CAS) describes "red leaves, loosened hour by hour". In the second and last stanza, he focuses on "the white memory of her".
That "white memory" has an almost searing quality, cutting through "all dead dreams of yesterday", reflecting the eternal symbolism of the plant referenced in the poem's title.