natural hair color

My hair is now pulled through a cap and frosted
very light blond with Matrix Colorgraphics
(purple) I love the color but even right after
it is done have dark roots that show to much now
that I am growing my hair out and wearing it up
most of the time. Honestly I don`t know what to
call my natural color, Haven`t seen it in years.
It is a very dark blonde or light brown with some
red to it, I know that I can not use ash blonde
colors on my hair it looks green.
I would like to go close enough to my natural
color to not have to color but maybe every 4
months or so just to give it some brightness or
highlights or something. I want to let my hair
get healthy so I can let it grow long.
I notice my hair breaking off after the Matrix
treatments and I don`t want to do this anymore.
(have been doing it for years but always have had
very short hair)
My hair is very fine slightly thin straight and
about shoulder lenght.
One of my main questions is how do I really match
my natural color?
How do I go about getting back there without any
more damage?
Thanks in Advance
Jetta

My hair makes me laugh some days.
Last March I decided that I wanted to go back to my natural color, dark blonde/light brown. I was also growing out my graduated bob hair style. I waited until May to get my haircut and colored b/c i wanted my stylist to have more hair to work with. She put lowlights of my natural color in my hair. About I week later I thought they were fading so she re-did them for me. During the summer I had them done 2 more times and by August I just got blonde highlights. Now that`s all I get.
The funny part is, when my hair is shorter, it grows like a weed, now it`s almost down to my t-shirt neck line and it`s growing so darn SLOW!!!!
So my advice is to go for the lowlights and deal with it for a few months, if you have shorter hair.