In The Scarlet Letter, red becomes symbolic of passion and life itself. The rose the grows beside the prison door is the first glimpse of color in the novel. The letter Hester wears to signify her adultery (a sin of passion) is deep red. As Arthur stands on the scaffold during the night, driven there by guilt for his sin, the giant red letter appears in the sky. As a color motif, red contrasts sharply with the colorless, gray Puritans and their stifling moral code.
In The Great Gatsby, green becomes symbolic of the fresh, uncorrupted promises of life. This is seen most clearly in the novel's coda in which Nick imagines the North American continent as it existed before it was settled, "a fresh, green breast of the new world," a place that "pandered in whispers to the last and greatest of all human dreams . . . ." Gatsby's dream is also symbolized by the color; the light at the end of Daisy's dock is a green light: ". . . [Gatsby's] dream must have seemed so close that he could hardly fail to grasp it."
I'd have to go with the famous poem "A Red, Red Rose" by Robert Burns. There the term "red" only appears twice, in that first line: "O, my Luve's like a red, red rose." There the meaning is first literal (many roses are red), but secondly, symbolic. The rose is most visible red when mature, and so this is a grown woman. A rose is red when flowering, which is to say, when ready to reproduce. (Not all symbolism is conscious…) The repetition makes it seem like he's pounding this point home, which is to say, like the redness is especially vivid. This evokes passion and intense sensation, as might cause a cheek to turn red.
Just a little bit of my opinion. Actually, both red and green are fresh and prominent colors. They symbolize for a thing that very good, maybe believe, hopefulness, or happiness. When red and green colors are used. It means that the author want we to think or to use a "fresh and bright feeling". However, for red color, sometimes it gives us a bloody and fearful thing. Maybe, that is an unhappy life and people think about or need the color of hopefulness -it is green color. I don't know which work you want to mention. But depend on your question I have such an opinion. Think of it. good luck!