Plant-based hair dyes work differently from chemical colorings. Chemical dyes penetrate the hair and color from the inside with an artificial pigment, while plant dyes stick to the outer layer of the hair.
Out of all plant dyes, henna is the most powerful in coloring, and it is the most permanent as well. It doesn't change the original color of the hair, but it colors the outer transparent layer of it. Every hair will be different from henna, because the natural hair color and the red of henna will make up the color together.
On brown hair, henna results in chestnut, and the lighter the natural hair is the more coppery it will be, for example on grey hair it makes an intense copper color. So you should keep in mind the percentage of grey hair while using it. On very dark hair, it results in brown hair with a slight red shine. There are other plants that can slightly affect the color.
Important information before and after dying with henna:
- You have to keep a 3-6 months break between using chemical dye and henna (it depends on how different the base and the dyed hair is) to prevent unexpected results.
- You can't use chemical products like dyes or permanent wave after henna dyeing (until it grows out)!