For healthy-looking hair color without the chemicals, try Colora Henna Powder. It's a natural henna powder that comes in several colors, including buttercup blonde, black, mahogany, and more. There's also a "natural" shade that conditions the hair without depositing any color. What it does: When the powder is mixed with water and applied to your strands, it deposits color on top of your strands (unless you choose the colorless "natural" shade). Not only does the henna change your hair color, but it also leaves your hair smoother, bouncier, and healthier. It takes at least an hour to process. For a richer hair color result, leave it on for longer than an hour. What else you need to know: This powder should be applied to clean, towel-dried hair.