It's even more than that, all you did was recolor the sprite. Furthermore, you didn't recolor everything.
Secondly, even if you didn't use the spray tool, the fact is your tiles are (eck... perfectly square) random color, and really don't look like grass. Seriously, just look at it, does that look like grass? No, I've never seen grass with light green squares every foot. Also, where the grass turns into something else, you definately need some sort of transition. Your doing exactly what Chapter 1 and 2 of Tsugumo's tutorial tells you NOT to do.