crimson
Purple Finch is not purple it's name has the word purple in it, doesn't mean it is purple it is actually red, brown and a little yellow
In the book purple is first referred to as the terrible and ugly color of a bruise as in someone who has been beaten. But then it is explained that a field of purple flowers can also be beautiful....
It symbolizes the beautiful purple folowers in the fields, and hoe they made someone who is aching, smile. =]