User blog comment:DeathZombi/Achievement Deficit Competition/@comment-5792287-20140104100554/@comment-24243917-20140104195859

Lukewarm is possible.

Steps :

(1) Remove all flower pots but the most back one in the middle lane

(2) Lose all lawn mowers but the middle

(3) Dr.Zomboss Will fire zombies at the middle lane only

( Note : You ca put a lot of plants in the lawmower side )