I've played about 15 levels now, so it should be enough to write a review for fairly.
I know that games of the same genre are bound to be alike one way or another but this one is very much similar to Plants versus Zombies (in case you don't know, PvZ2 is out by the way!), like the others have complained about. But the positive side is that, this one isn't half bad either so at least you made an effort despite it being clone-ish. *COUGH* I've seen worse on NG before *COUGH*.
Art: 4 stars
SFX/BGM: 4 stars (repetitive)
Controls: 5 stars (use of keyboard function optional)
Gameplay: 3.5 stars (it gets challenging quickly, but no 'original' content)
Overall: 4 stars (4.1 stars)
P.S.: The snails sound like minions, don't they?