To dream that you are mowing the lawn suggests that you to need make some major reevaluations of your goals and life path. 

In particular, to dream that you are mowing a football field refers to your desire to make a fresh new start in some competitive area. Perhaps you have been overly competitive or passionate and need to tone it down. If flower heads were spitting out of the lawn mower, then it means that you need to show your softer side.