Rodney Wayne Creative and Education Director, Newton Cook has the answers.

The short answer is that it depends on your tendency to go brassy, whether your hair receives colour easily, or is thicker and more coarse in texture. It also depends on what result you want. On top of this, different products have different recommendations, so always read those labels. In general, if youāre a warm blonde, leave in longer than if youāre a cool blonde ā makes sense, right?
Purple shampoo is popular not only with coloured blondes, but also natural blondes, those with grey hair that tends to yellow, and even people who have darker hair with brassy tendencies. Newton concludes, āYour hair colour is as individual as you are. I invite you to visit and talk with the colour experts at your nearest Rodney Wayne or Shampoo 'n'Things about your specific hair care requirements. Itās worth taking that little extra time to ensure you are bringing out your beautiful best.