Spike

Spikes are a type of weapon against zombies. Only two plants fire them, the Cactus and the Cattail. They are red and pointy, similar to the Cactus's thorns and the tip of the Cattail's tail.

Overview
Spikes do the damage of a Pea and also have the ability to shoot down Balloon Zombies. The Cactus shoots Spikes at the normal firing rate down its own lane, whereas the the Cattail can shoot down any lane and shoot two at a time.

Trivia
The Cattail is the only plant that can shoot anywhere by itself. The Cob Cannon can shoot anywhere, but not on its own.