text: Extreme How-To - January/February 2010
  Shawn Joslin tests the concrete for washing. He feels for movement in the aggregate underneath. If it's stable, it's ready.
  to the game to help the hose. Get the timing right, and it's almost as easy as washing the driveway.
  Test the area where you started pouring and see what it looks like. If you can't avoid blasting gravel out of the walkway, then it's a bit too early. When you can proceed without rolling gravel down the walkway, it's time.
  Carefully strip the forms and go for it. Systematically move to the adjacent area as gravel in the impact zone is exposed but not removed. Handle your spray in a way that doesn't create a streaking pattern. Go over the entire
  A water hose with good pressure is the preferred method for washing exposed aggregate.
  LANDSCAPING AND OTHER HAZARDS
  Green (uncured) concrete is susceptible to staining. Be careful not to get mud or landscaping supplies on the new walk. Stains at this point may never come out. Wait 10 days or so before landscaping around your new walkway.