What temperature should the water be to mix henna? I used to use very warm water when using tea bags. Today I used room temperature water with lemon to mix my henna. I recently read on a link placed in one of the threads here of a woman who uses very hot water to mix her henna but I've also heard that hot water isn't good for henna. Does it matter the temperature of the water used to mix henna? I was always afraid to use lemon because I heard it makes the hair very dry but decided to give it a chance anyway. The only obvious downside I can see is waiting hours and hours for the henna dye release, tea only takes a few hours. Are there specific benefits to using lemon?
Heat makes henna release dye quickly and demise quickly. Boiling water gives a stain that fades rapidly to a light dull orange - for me, it faded pretty much in 2 weeks.
A little bit of lemon plus mostly water won't dry your hair. I don't advise using all lemon juice for people with damaged hair as it can make it more brittle, but a spoonful shouldn't do that.
Assuming you're using cool liquid, water will give rapid dye release (usually within 1 hour) and the more acidic the liquid is, the longer it will take to release dye. All lemon juice may not peak until close to 24 hours. Water with a splash of lemon will be much faster, maybe 2-6 hours.
The advantage of using a cool acidic liquid is it slows down dye release and demise enough that you have time to get it in your hair, have it release more dye while it's on your head, which will form a more permanent bond with your hair's keratin, and you can also freeze leftover paste and they'll still be good (often they'll be even better) when you thaw it out. When you use plain water or anything warm, the dye doesn't stay usable as long.