Cold-shroom

This plant is like a toned-down Ice-shroom. It doesn't freeze zombies, it just slows them. It also does no damage at all, but zombies very weak to cold weather will take damage from it. It has three advantages over the Ice-shroom. One is that it costs much less, and a second is its fast recharge. The third, and also the most notable, is the fact it slows zombies for 50% more time. It is also rather lightweight.