How long to leave hennahut henna on?

[Speckla]

I usually get my henna on mehandi.com and I leave it on for about 18 hours.
I tried hennahut red and I've had it on my head for about an hour which is what the instructions said. My hands are flaming orangy/red due to not using gloves + instant dye release.

[ellen732]

I usually leave the Henna Hut Brown on for an hour, but it says it can be left on up to 3 hours, just expect darker results.

[Speckla]

Thank you. I am trying to get the reddish possible color.

[jojo]

I normally leave henna on for 4 hours as it gets so heavy on my head it feels like my necks going to snap! oh and orange hands, been there it does g(l)o eventually!

[Speckla]

I managed two and a half hours. :) My bangs (mostly grey) are a bright, bright red. I'm excited to see the rest of it. I saved some and froze it incase I have to do a root touch up.