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This article is about using henna and indigo to enhance or deepen naturally dark hair, or to shift from black to a lighter brown, not about covering grey. If you're looking to cover existing grey hair, our article on natural ways to cover grey hair with henna covers that specifically. For the full step-by-step method, troubleshooting, and aftercare across every shade, see our complete henna and indigo guide.

Why the ratio matters: choosing your shade

The ratio of henna to indigo, and how long each step is left on, is what actually determines your final shade. Decide your target before you mix, since adjusting mid-process isn't possible once the paste is on your hair.

For a light to warm brown, chestnut or auburn territory, use 3 parts henna to 1 part indigo. Leave the henna on for 3 hours and the indigo for 30 to 45 minutes. This is best for people who want warmth and depth without going too dark. For a medium brown, the natural brown or milk chocolate range and the most popular shade among Satthwa customers, use 2 parts henna to 1 part indigo, with henna left on for 3 hours and indigo for 1 hour. It gives a natural-looking brown that blends well with dark Indian hair specifically.

For a dark brown, dark chocolate or coffee territory, use equal parts henna and indigo, 1 part to 1 part, with henna left on for 3 to 4 hours and indigo for 1.5 to 2 hours. This sits close to natural dark brown on black hair, deepening and enriching the colour without going fully black. For near-black with warm brown undertones, use 1 part henna to 2 parts indigo, with henna left on for 3 to 4 hours and indigo for 2 to 3 hours. This suits people who want black but with the warmth that pure indigo alone doesn't give.

Results vary by starting hair colour, and it's worth being upfront about that. On naturally black hair, lighter browns are harder to achieve, since the existing dark pigment limits how warm or light the result can go. On naturally dark brown or lighter hair, the full range above is achievable.

What you need

You need henna powder, indigo powder, lukewarm water, lemon juice or apple cider vinegar, a non-metallic bowl, since metal reacts with henna and dulls the colour, gloves, a shower cap, and an old shirt. The lemon juice or apple cider vinegar matters more than it might seem: the acidity helps release lawsone from the henna, giving stronger colour. Avoid hot water specifically, since it degrades the dye before it ever reaches your hair.

The two-step method: step by step

Step 1, prepare and apply henna. Mix henna powder with lukewarm water and a splash of lemon juice to a smooth yoghurt consistency. Cover and let it rest for 6 to 8 hours, or overnight. This dye release step is critical, and skipping it gives noticeably weaker colour. Apply to clean, dry hair in sections, starting at the roots, and cover with a shower cap. Leave on for 3 to 4 hours depending on your target shade from the ratios above, then rinse with water only, no shampoo at this stage.

Step 2, prepare and apply indigo. Mix indigo immediately before use. Unlike henna, indigo begins oxidising quickly and must go on fresh rather than resting. Mix with lukewarm water to a smooth paste, and apply to damp, henna-treated hair within 20 minutes of mixing. Leave on for the time required by your target shade, then rinse with water only. Wait 48 hours before shampooing, since this is when the colour oxidises and deepens to its final shade.

Why the 48-hour wait matters

Indigo colour isn't stable immediately after rinsing, it continues oxidising for 48 hours afterward. Hair that looks medium brown right after rinsing often deepens to a proper dark brown by day two, which is why judging your result too early leads to unnecessary disappointment. Shampooing before that 48-hour window strips colour before it has fully fixed into the hair shaft, leading to faster fading than the process is actually capable of. Use water only for your first two washes after colouring.

Henna and indigo vs chemical dye: the honest comparison

Chemical dye does a few things better, and it's worth saying plainly: precise, predictable shade control, it works on any hair type without the variability henna and indigo carry, and the process is considerably faster. Henna and indigo is the smarter choice when healthier hair matters more than exact shade precision, when scalp sensitivity is a concern, and when a natural, gradual fade without a harsh demarcation line and a genuine long-term conditioning effect on the hair itself are worth the extra time.

Troubleshooting: why brown came out too dark, too warm, or patchy

If the result came out too dark, indigo was likely left on too long or the indigo ratio was too high relative to henna. For your next application, reduce the indigo proportion or leave it on 30 minutes less than you did this time. If it came out too warm or orange, there wasn't enough indigo, or the indigo had already started oxidising before it went on. Make sure indigo is mixed immediately before use rather than prepared in advance.

Patchy coverage usually means hair wasn't fully saturated during application, or indigo was applied too long after rinsing the henna out, letting hair start to dry in between. Apply indigo immediately after rinsing henna, while hair is still damp, to avoid this. If colour faded too quickly, you likely shampooed too soon after application, or you're using a sulphate shampoo that strips natural dyes faster than a gentler formula would. Use a sulphate-free shampoo and hold off on washing for the full 48 hours described above.

If grey strands aren't matching the rest of your colour, that's because grey hair takes henna and indigo differently from pigmented hair. It absorbs henna strongly, sometimes going more orange-red than intended, but can resist indigo more than pigmented strands do. Applying henna to grey areas first and leaving it slightly longer than the rest of your hair helps close that gap. For full guidance on grey coverage specifically, see our grey hair coverage article.

Not sure which ratio suits your hair? Our henna and indigo shade finder walks you through it based on your starting hair colour and target shade.

Frequently asked questions

Henna and indigo give you control over your shade that most natural alternatives don't: adjust the ratio, adjust the result. The two-step process takes time but the colour lasts, conditions as it colours, and fades gradually rather than harshly. With pure powders and the right ratios, the result is genuinely beautiful.