How long does the colour last and what makes it more or less intense?

The colour deposits on the outer hair layer and washes out progressively, typically lasting 3–8 washes depending on how often you shampoo and how porous your hair is. On medium brown hair you will usually see a cool plum reflection that adds depth rather than a strong colour shift. On light blonde or pre-lightened hair the same pigments appear much more vivid because the lighter base lets the tone show through clearly. Gray and very porous strands also grab pigment more aggressively, so the result can look deeper or brighter than expected.

You control intensity mainly by leave-on time. A quick lather-and-rinse (1–2 minutes) gives a subtle refresh; leaving the foam on for 5–10 minutes builds a noticeably stronger plum tone. Because the product does not use oxidative developers, the colour cannot lift your natural shade — it only adds tone on top of what is already there. Hard water, clarifying shampoos, and frequent heat styling accelerate fading. If you want the reflection to stay visible longer, wash with cool water, use a sulphate-free shampoo between applications, and limit hot-tool use on the lengths.