That's an AWESOME idea! It's got such a great colour, hasn't it.
I asked auntie google and even found a recipe:
How to dye your hair red naturally
The main issue I have is the hour of sun they want... i do not live in a very sunny area
EDIT: I am wondering if it also works when you create a beetroot/carrot mash and put it on your head. It might hold better in your hair than the liquidy juice.
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