Why purple

a little poking around turned out some revealing info, quite similar to what we discussed:

Shug Avery, a self-confessed sinner who is denounced by the churchgoing community, defends God. God is not “him” to her, but rather “it.” She espouses a pantheistic view of the world in which all nature is God, and God appears in all nature. God is a joyful and loving being. The novel’s title reflects this as Shug tells Celie that she thinks God may become angry when people walk past a field and fail to appreciate the color purple. In her view, God appears in church only when the people themselves bring him in. Her religion stresses love, compassion, and pleasure.

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The color purple itself becomes, along with Celie's sewing, the central symbol in the book. Suggestive of royalty, creativity, surprise, it becomes for Celie symbolic of the wonder of the creativity of God. The first new dress she owns (not a hand-me-down), she wants to be purple. Purple not available, she opts for blue. When, at the end, she finally has her own house, she sleeps in a room painted purple. The pants she sews for Sofia have one red leg, the other purple. Purple is also the symbolic color of lesbianism; Celie's passionate love for Shug Avery is one of the poignant centers of the plot. When Shug leaves her for a young man, Celie is so crushed she can only communicate to Shug by writing notes: “I pray to die, just so I don’t never have to speak.”