I started my Ayurveda regimen 5 months ago. My biggest concern was that the powders would darken my hair. I didn't want this because I loved my natural hair color. It has always been this reddish brown color ever since I was a little girl. It darkens in the fall/winter and lightens back up in the spring/summer.
When I first began my regimen I was doing it 2 to 3 times a week, but then cut back out of laziness. I never saw my hair darken and was like great. A couple of weeks ago someone asked me in another post if hibiscus changed my hair a wine color. I was like "No". I've never seen my hair change color. Well last night I did my regimen. I made my tea rinse of (1 tsp: Shikikai, Brahmi, Fenugreek, Maka, 2 tps: Hibiscus and Amla). I left my mix on for the usual amount of time 30 mins to an hour. Then rinsed, applied my leave ins, and seal. I paid attention this time and low and behold I did notice that my hair had a winish tint to it. It is very subtle. I wouldn't have noticed at all if it hadn't it been brought to my attention. I can really see it when I am in the sun light. I love it.
After may attempts with my crappy phone this was the best pic I could get to show the winish tint to my hair. I personally love it. For those that don't want the color change then you may not want to use hibiscus or not leave in on your hair for long periods of time.
ETA: I think believe that the color would have been brighter had I used the hibiscus powder alone. Mixing the hibiscus powder with the other powders most likely helped to make it more subtle and balance it out.