Organic Henna Leaf Powder

Lawsonia inermis

There Is No Orange
in the Leaf

Henna's colour isn't sitting in the powder waiting to come out. The leaf stores it as a colourless precursor, and it only turns orange once water gets to work on it — in your bowl, and then on your head.

What it does next is what makes henna different from every other plant in our range: it bonds to your hair, and stays until the hair grows out. This page explains how, and shows what we saw when we tested it.

Mix

1 : 3

powder to water, by weight

Paste pH

4.82

our measurement, at 78.9°F

On the hair

Keep it wet

dry paste stops giving colour

Organic henna leaf powder with fresh Lawsonia inermis leaves

How It Colours

Released in the Bowl,
Bonded on Your Hair

Henna's pigment is called lawsone. It doesn't exist as lawsone in the dry leaf — it has to be released, and then it has to reach your hair while the paste is still wet.

Hennosides

In the dry leaf · colourless

The leaf stores its colour as hennosides — lawsone with a sugar attached. Nothing about them is orange.

→water, mild acid, the leaf's own enzyme

Lawsone

In the paste · orange

With the sugar split off and oxygen around, the orange pigment forms. It travels in the water of the paste — which is why the paste must stay wet.

→contact with the hair

Bonded to keratin

On the hair · permanent

Lawsone reacts chemically with the protein of your hair. It attaches rather than resting on the surface, and stays until the hair grows out.

It doesn't all release at once

A published study measured how much lawsone came out of henna leaf powder soaked in water, over time. Release is slow:

30 minutes20%
1 hour47%
About 4 hours93%

The release doesn't stop when the paste goes on your head. It carries on there, for as long as the paste is wet. That is why we tell you to mix and apply straight away and give the time on your hair instead — and why henna-led shades ask for longer than the others. Our own test, below, shows what an extra hour does.

Why henna lasts longer than other plant colours

Most plant pigments only cling to hair loosely. Lawsone forms a chemical bond with it. In published comparisons, colour from black-bean anthocyanins — the same pigment family as hibiscus — lasted only four washes. Henna wears down as the hair itself does.

Why it likes a slightly acidic paste

The release of lawsone happens under mildly acidic conditions, and lawsone bonds well to keratin in the same range. Our henna paste measured pH 4.82 with nothing added — the leaf brings its own acidity.

Sources: hennoside to lawsone chemistry and the keratin bond are described in the henna literature (e.g. Dallmann et al., International Journal of Cosmetic Science, 2026). Release over time: Estimation of Lawsone Release from Lawsonia inermis Leaf Powder and Dye Uptake on the Hair, Research Journal of Phytochemistry.

What We Tested

One Hour or Two.
Dried Fast or Slowly.

We coloured white swatches from the same bowl of paste and changed two things: how long the paste stayed on, and how long each swatch stayed damp afterwards. These are the results 90 minutes after rinsing.

Paste

1 : 3 by weight

Paste pH

4.82 at 78.9°F

Mixed

Applied straight away

While on

Covered, kept wet

Henna leaf paste in a glass bowl with a pH meter reading 4.82 at 78.9 degrees Fahrenheit

The paste, freshly mixed. pH 4.82 with nothing added.

Five henna-coloured swatches 90 minutes after rinsing, all orange to red-orange, beside an untreated pale swatch

90 minutes after rinsing. From the top: 1 hour fan-dried, 1 hour air-dried, 1 hour towel-wrapped, 2 hours fan-dried, 2 hours towel-wrapped. Untreated at the bottom.

On the hairAfter rinsingDamp forLightness (L*)Hue
1 hourFan5 min35.565° · most yellow
1 hourLeft to dry60 min27.156°
1 hourTowel90 min31.057°
2 hoursFan5 min28.360°
2 hoursTowel90 min25.455° · most red

Measured from the photograph above, not with a colour meter. Lower lightness means deeper colour; a lower hue angle means redder, higher means more yellow.

1

Two hours went deeper than one

Compare like with like and the longer application is deeper both times — fan-dried 35.5 to 28.3, towel-wrapped 31.0 to 25.4. The release carries on while the paste is on your head.

2

Drying didn't change the direction

All five are orange to red-orange. Nothing went green, blue or violet. Indigo, tested the same way, had already split into three different colours by this point. See the indigo test →

3

Fast drying looked a little lighter

The two fan-dried swatches came out slightly lighter and slightly more yellow than their towel-wrapped partners. The difference is small — whether it lasts is what the next photographs will show.

What this is and isn't. One swatch per condition, on white hair, photographed once at 90 minutes. Henna is widely reported to deepen over the first one to three days, so we are photographing the same swatches again at 24 and 72 hours and will update this section with what we find.

Henna and Indigo

Two Leaves, Two Very
Different Timetables

Both store their colour in a colourless form, and both need water to release it. After that they behave in opposite ways — and knowing which is which explains most of what people see after colouring.

HennaIndigo
Stored in the leaf asHennosides, colourlessIndican, colourless
PigmentLawsone — orangeIndigo — blue (plus red-violet indirubin as a by-product)
When the colour formsIn the paste, while it is on your hairMostly after you rinse, as air reaches the hair
How it holdsBonds chemically to keratinHeld in the outer layers, not bonded
Longer on the hairDeeper — our test, 1 hour vs 2More time for the colour to take
How you dry it after rinsingLittle effect — stayed orange whichever way (our test, at 90 min)Decides the colour — blue if kept damp, red-violet if dried fast
Paste pH, measured4.826.28
FadesSlowly, as the hair wearsSooner — usually first to go

So with henna

The work happens while the paste is on. Keep it wet, give it time, and by the time you rinse, the colour is attached.

And with indigo

The work happens after you rinse. That is where the green stage, the drying rules and most colour surprises come from. How indigo colours →

Using It

Three Ways People Use Henna on Its Own

Henna only ever adds warmth, and it only ever deposits — it cannot lighten hair. Within that, it is more useful than it first looks.

How to apply it

  1. 1

    Wash, skip conditioner

    Towel-blot until damp, not dripping.

  2. 2

    Mix 1 : 3, apply straight away

    Powder to warm water, by weight. Stir for two to three minutes; it looks too dry at first.

  3. 3

    Cover it and leave it

    Film, then a cap. At least one hour; two goes deeper. Don't let the paste dry.

What about letting the paste rest first?

Many henna guides tell you to leave the paste for hours before applying. That is advice for henna on its own. If your colour contains indigo, mix it and use it straight away — indigo doesn't wait. And you don't lose anything by skipping the rest: henna keeps releasing on your head, which is why our two-hour swatch came out deeper than the one-hour one.

It stays

Henna bonds to the hair. Start shorter than you think — adding more later is easy; taking warmth away is not.

Patch test first

A small number of people react to henna. Test a little paste on your skin 48 hours before a full application.

Plain leaf only

Products sold as henna have been found with metallic salts or PPD added. Ours is one ingredient. Our certifications and lab report

Shop Henna Leaf Powder →

Not sure henna is what your hair needs? Send us a photo at info@radicousa.com — we answer ourselves.