A game with an original concept!
I've not seen such a game like this that can vary well in difficulty with such a crazy set of rules!! Btw, your Old West challenge level (May 18) is probably one of the most difficult ones (I was the only one on there at the time.)
Unfortunately, this game is with its own flaws of its own. Just like how there's a preview of incoming crops, there should be a preview of incoming enemies, and if you think that's pretty useless, so is the crop meter because it's fairly random. Also, the area lasso that you see when you "box" monsters and crops could use more design and "attitude" to it instead of being a plain ol' boring shading. You probably could have better explained other concepts in the game such as the magnitude of plop spreadage when you create new plops.
While lack of control degrades this game, your talents as a game creator excel very well!
A 10 in Style! Congratz!!