The change in color I would assume is because the hair is many years old and from coloring it you altered the hair structure...Even though the color is gone, the damage still exists. Depending on the color of your hair you could do coffee rinses or things of that sort...I am sure someone will pop in and tell you all about them. Also even though it would be one heck of a hassle with all that hair, there is always henna. Sorry I'm no help.

herbal henna, definitely!

Love the repies Ladies, Thanks! But where do I get this "henna", and after I do it do I have to continue to do it as if I was using regular hair dye. And yes in the past it was myself  that did the dying.

Hi SittyKitty!

I'm also a henna proponent.  I've never tried Morrocco Method, so I can't compare the two, but I like Avigal henna which I order through Ball Beauty at http://www.ballbeauty.com/avigal-henna.htm. ; I find that the color is basically permanent on my ends, although it does fade a bit, and I only need to touch up my roots.  Since you're just trying to match the ends to your natural color, touching up roots won’t be a problem for you. 

You can also mix various colors of henna, to get a color that is close to your natural shade.  I myself like a half-and-half mix of red and copper. 

For knee-length hair, you're going to need quite a bit of mud, depending on how thick your hair is.  My hair is thin, fine and almost waist-length, and I use about 9 ounces per application.

Bear in mind that it will be a huge pain to wash out of all that hair, but if it matches your ends to the rest, it should be worth it.  I recently used Anais Satin's COW (a combination of conditioner, shampoo and water, shaken up into a froth) to wash out the henna, and it worked better than anything else I've tried.  If you have a hand-held shower attachment, that also helps.  I kneel down by the tub and rinse with the attachment, which is a lot easier on the back than leaning over in the shower.  Also, henna will stain your skin, so you need to be careful about where it goes.

Feel free to ask any questions you may have, there are a lot of us henna-heads on here!