I am 36 and have quite a few grey hairs at my front hairline, which are very noticeable when I put my hair up. I have black hair but whenever I have used indigo from other brands it just doesn’t work! I have very resistant grey hair. If you do too maybe you can try what I found what works. I have no problem getting henna to stick to my hair if I use dry shampoo. I use a powder form of dry shampoo where I have grey hair. I then apply just henna to that. After 3-4 hours I wash it out with the Soapnut hair wash. Then I apply the indigo and leave it on for about 2 hours Sometimes it doesn’t stick, so it maybe requires a repeat application, but it really does work! I just washed my hair out after having the indigo in and it looks like this. Prior to this photo my grey hairs were bright orange and did not look blended!
Make sure your hair is super clean when applying indigo. Also, if it didn’t work the first time, just do it again a few days later. It will work eventually. I was about to give up on doing henna/indigo but I finally found what worked for me. I wanted to post this review for someone else who may be in the same boat!