When you're engaged in war with the likes of plantlife or the animated undead, you can't just rush into the fray. Only a fool would do that. No, you have to study your enemy, and more importantly, know thyself.
This gameplay video of Plants vs. Zombies: Garden Warfare should help with that. It explains the abilities of each class type, some of the different modes, and how the game's economy works. So, now you have no excuse to not be as prepared as possible for this self-proclaimed weird shooter.