Lvls 1-14 easy peasy. Lvl 15 just annoying, like when a platform game has a really annoying jump that is almost impossiable to make and eats up 25 lives and you have to restart.
I liked the concept of the game, it adds a little somthing new to the defense series. I did not like however, the fact that you can't make up a decet strat because your flowers move which ever way they please and mess up any chance of an organized and strategic attack.