darkening hair with sage tea

[la_guillotine]

I found something in the memories that mentioned using sage tea as a natural hair darkener. Has anybody actually done this and does it really work? Or what about coffee grounds...if you have successfully used one of these methods, please tell me how you did it (how long to leave on, etc)

I have had bad experiences with henna and stuff like Herbatint was too subtle and/or never lasted long enough to make it worth the $$. And I really, really want to stay away from chemical dyes.