The Welsh side head into the competition on the back of defeats to Argentina, Samoa, New Zealand and Australia in the Autumn internationals, and Edwards believes that they can't afford to slip up.
"In the autumn, it took us two-and-a-half games to get going, to get up to the speed of international rugby, in all aspects of the game," Sky Sports News quotes Edwards as saying.
"But it took us two-and-a-half games to get to that level. We can't afford to do that this time. We have to hit the ground running."
Wales begin the defence of their Six Nations title against Ireland on Saturday.