Moon-shroom

Overview
The Moon-shroom is a plant obtained after completing the second level of The Moon. Moon-shrooms are identical in function to Puff-shrooms, except that they can be planted on the moon and don't disappear over time.

Suburban Almanac Entry
The other plants wonder how Moon-shroom can withstand the lack of air and warmth on the moon’s surface. “Guts,” Moon-shroom responds, “I ain’t one of those whiny types. I’m a fungus from cap to pore. I’ll even tough it out on the surface of the sun if I have to.”

Can only be planted on the moon.

Strategy
Moon-shrooms are essential to survive early waves of zombies on the moon, as other plants cannot freely be placed on its surface without the Vac-shroom. It is recommended to plant as many Moon-shrooms as possible down, as they are free and don't disappear. Moon-shrooms are also very useful to combat Alpha Clone Zombies, as they can quickly cover multiple lanes.

Trivia

 * The Moon-shroom is the only free permanent offensive plant in Plants vs. Zombies 2.