I had witness a large commercial greenhouse using a BIG cement mixer to mix their soil, so suggested it to our neighbor at the Lake who had laborously been trying to mix soil in his wheel barrel. He was so delighted and the idea had never occurred to him. He has the sort of cement mixer that I know you are looking for, Catherine. It certainly works well, but can't say that I know where to tell you to begin to look for one. Barb Barb Rothenberger Columbia, Mo. See our pictures of the Philadelphia flower show http://www.geocities.com/PicketFence/3257/