Dark Hair, Gray roots! Colormark?

After one week of coloring with Loreal professional at home coloring and Gray magic, my gray hair shows up. I am currently using a crayon for touch ups which I hate. I am 35 years young so this advanced graying is pretty embarrasing. Has anyone tried Colormark? I do not wish to re-dye my hair roots with actual hair color within a week because that defeats the purpose. 

I also use 20% peroxide before coloring wich softens the gray and absorbs the hair color on all my stubborn gray for  complete coverage. Anyone have any other in-between ideas or suggestions? I think Colormark is the way to go, but pricey! It is used by celebs and has appeared in every magazine from fashion to pregnancy.  

I have also read to apply color only to the roots, after doing this for 6 months and experimenting to find the right color and technique that would grab the gray, my mid section and ends of hair looked ashy (green) and needed refreshing. I ended up dying all of my hair with Loreal excellence cream in light Golden brown 25-30 minutes on roots with gray magic also. NO PRETREATING WITH PEROXIDE this time. Left 10 minutes on ends to refresh color. Took very well,  but roots look very light compared to the rest of the hair. The light golden brown in any brand comes out almost dark brown on my naturally curly hair. Needles to say the green is still there. I will try the demi and maybe buy a red toner to for the ash in my hair.