Possible Clues:

• That sounds as if a nothing can die
• A nothing at all that may die, so it sounds
• Dye used in blue jeans
• By the sound of it, this might die for a shade of a nothing
• Source of dye popular over in Alabama
• Shrub providing indigo
• Not a thing will die, by the sound of it
• Be sick having swallowed new dye
• It produces dye by a river out East
• Actress at first put on nothing in indigo