Growing “green” grass is somewhat of an oxymoron due to the fact that most of us use pesticides and synthetic nitrogen to accomplish that end—and that is dangerous.  At Harvard they have switched their lawn care to organic methods like compost and compost tea and the results have been stunning.   The microbes that now feed the grass have turned it healthy, lush and truly green NATURALLY—and that is wise.  www.uos.harvard.edu/fmo/landscape/organiclandscaping