You're probably better off freezing it. At the aforementioned website they recommend only refrigerating it briefly (up to 24 hr.s). I think the fridge speeds up henna's demise relative to freezing. The fridge storage thing might merit further research though, just in case the ppl at hennaforhair are wrong.

One thing to consider too (in case you don't know): a lot of people report that henna mixtures that have been frozen produce a stronger (deeper red) dye. I assume this applies to henna mixtures that oxidized long enough for dye release. ... Just something to consider in case you want to keep your current shade of red w/out it darkening.
Originally Posted by Korkscrew
Oops. I meant to type freeze. It's sitting in my freezer right now. All this henna stuff is very word of mouth on the internet, but every generally seems to be right. It would be nice if there seems to be more research.

So far my new henna color (done with henna that was frozen for 2 months) seems very similar to the old one. I did want a richer, darker color though. It's very hard for me to tell, but it seems similar to me. After this I am planning on just doing root touch ups, so hopefully my head will stay at this darkness of red.

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