Squash

The Squash is a one-time use plant that attacks zombies in an adjacent tile by squashing them.

The Squash appears to be loosely based on the Butternut Squash[1], one of several species of Cucurbita maxima.

Usage
When planted, the Squash waits until it sees a zombie in an adjacent square (to the left or right), then it pounces, destroying itself and dealing a large amount of damage to all zombies on that square.

Suburban Almanac Entry
Squash

Squashes will smash the first zombie that gets close to it.

Damage: massive

Range: short range, hits all zombies that it lands on

Usage: single use

"I'm ready!" yells Squash. "Let's do it! Put me in!  There's nobody better! I'm your guy! C'mon! Whaddya waiting for? I need this!"

Cost: 50

Recharge: slow

Standard Levels
The Squash is a good plant to use in early setup against that one zombie or tight group of zombies that is too strong for the current defense or that managed to sneak through. However, plant slots are generally too valuable for this plant to be of frequent use, though they are good against Gargantuars and Zombonis in emergency situations, and can be used on Survival: Endless after you finish your setup. The Bobsled Bonanza mini-game is one level that the Squash really shines on, however, because of its relatively cheap cost and ability to destroy a Zomboni or entire Zombie Bobsled Team in one hit. It may also be of use on the Column Like You See 'Em and Pogo Party mini-games.

Vasebreaker: Another Chain Reaction, Ace of Vase & Endless
These levels absolutely require that you use the Squash, due to the presence of Gargantuars. Whenever you see a Gargantuar, hit it with two Squashes as quick as you can. Don't forget you can even plant the squash directly under the Gargantuar, and it will Squash the giant zombie before it has a chance to react.

I, Zombie puzzle games
There are several I, Zombie levels with Squash. Make sure you use cheap zombies whenever you can, and remember that the Gargantuar can be easily taken down by two of them in the same lane.