How long do you wait to wash/CO after henna?

[WednesdayAddams]

It's been a while since I did a straight henna and now I just can't remember. Is 48 hours enough?

[paulownia]

Yes, 48 hours
If I do henna on Sunday I usually wash on Tuesday.

[Nightshade]

You honestly don't have to wait at all unless you're using a cassia-heavy blend and a gentle shampoo.

I use a blend that's more than 50% cassia and I shampoo my henna out without issues

[WednesdayAddams]

Thanks to both of you.

[luthiene]

You honestly don't have to wait at all unless you're using a cassia-heavy blend and a gentle shampoo.

I use a blend that's more than 50% cassia and I shampoo my henna out without issues

Why would a gentle shampoo be more of a reason to wait to wash vs using a harsher shampoo?

[paulownia]

Why would a gentle shampoo be more of a reason to wait to wash vs using a harsher shampoo?

I'm also curious, why?
Generally using shampoo after henna is not necessary if hair was shampooed before the treatment. It's recommended to clarify and chelate before henna and cassia. So if the hair was washed before - and herbs are clean- there's no need to shampoo after.
A good mermaid soak helps to remove all henna particles from the scalp and hair.
If one applies henna on unwashed, dirty hair ... that's another thing.

[Nightshade]

Why would a gentle shampoo be more of a reason to wait to wash vs using a harsher shampoo?

I'm also curious, why?
Generally using shampoo after henna is not necessary if hair was shampooed before the treatment. It's recommended to clarify and chelate before henna and cassia. So if the hair was washed before - and herbs are clean- there's no need to shampoo after.
A good mermaid soak helps to remove all henna particles from the scalp and hair.
If one applies henna on unwashed, dirty hair ... that's another thing.

The main reason is that shampoo creates air spaces in between the hair, which allows the henna mud particles to move into those spaces and away better than it will with just conditioner, which can (especially with very thick hair) slick down into sheets that are more challenging to rinse.

Henna is pretty bomb proof, so it's faster and you get a better mud removal with shampoo without loss of color. You can of course use whatever shampoo you'd like, but when rinsing out something that can be more sensitive, like cassia's golden color, a harsh shampoo can pull some of the color, but a gentle one will (generally) not.