Indigo Summer: Ultra-Mild Cleanser to Preserve Color & Shine. Indigo Summer Colour Protection Shampoo s a gentle cleanser formulated to protect and enhance natural or colour treated hair. This formula, rich in essential fatty acids, helps replenish valuable lipids, lost through chemical processing. Indigo Summer Colour Care Shampoo limits tonal changes that result from hot styling tools, environmental exposure and chlorine or mineral build-up. Indigo Summer Colour Care Shampoo will leave hair looking vibrant and feeling soft, shiny and manageable. All Prairie Naturals hair care products are enriched with pure, natural aromatic plant oils.