So, am about to buy a henna/indigo kit from henna-boy to help cover some of the crop of grey hairs that have suddenly cropped up around my hairline (dammit). On a previous thread somewhere on here, someone mentioned Amla powder as the product to use to help the dye 'take' on the grey hairs.
Just to be sure, I emailed customer services, but they've advised me to use a different product first. (Shikakai powder). Even their own website differs from this- only the description for the Amla mentions white/grey hairs at all.