There was a recent thread about haircolor and I just realized that I'm doing my roots at least every 3 weeks. Not from the color fading but because my hair has decided to take off and grow like weeds. I'm not complaining, it grows slow to begin with but is this common in our 40's to have a growth phase? I thought it was supposed to slow down. I'm seeing a 1/4inch to 1/2 inch growth.