THIS GUIDE WILL GET YOU THE ACHIEVEMENT BEFORE STARTING THE MAIN GAME
This can be done on the very first tutorial level. when you have only one strip of lawn and only one lawnmower to activate.
When directed to plant two pea shooters, plant them in the two nearest spots next to the hedge. Then the wave will begin, 2 or 3 zombies. they will eat through the peashooters and continue toward the house. However they will not make it before the final wave starts. Leave the zombies to make their way to the lawnmower, allowing more zombies onto the screen. When the lawn mower is activated it should take all but one zombie out. Simply plant another peashooter right next to the house to kill the last zombie.
Check my gamer card,it's the first achievement i got. I unlocked this before i had planted ten peashooters!GammyGreenGiant's achievements in Plants vs. Zombies (WP)
I don't think it'll work for the console version because the achievement description specifies "when all 5 lawnmowers have been activated....".
Any neg votes, comments, suggestions or questions feel free to leave a comment or PM me