My Natural Solution to dying my Grays is Hendigo = Less Henna more Indigo.
It sufficiently covers my Gray. It can be time consuming and messy but it works like a Charm every single time.
Done personally with Store bought solutions, so this is the only way for me to go.
Is that one product or is it a combo of henna and indigo? How do you use it?
If she has a lot of grays, I wouldn't go all the way back to black. It often looks too harsh and unnatural. I would instead go for a semi-permanent dark brown hair dye that lets the grays shine through so to speak.
I use henna + indigo like the ladies above here, but I don't think it will look nice when I -have 70-80% gray.
You want to create as little contrast to the new growth as possible...
I use demi permanent natural black from sallys beauty supply
thanks. how often do you use it?