Mine has been on for over a month. I've mowed three times already and fed twice.

Here's my lawn on this day last year (I didn't take another photo this year but it looks about the same right now) when I took a photo to post to Facebook with the line: "Attention neighbors: it's April & you already lost Lawn Wars 2015. Better luck in 2016"

The front with my neighbor's postage stamp for comparison purpose:



The back but harder to see the neighbor's back yard for comparison:



...they didn't fare much better this year either.