There are 12 achievements worth a total of 200 points
Complete adventure mode
Collect all 49 plants in the game
Grow the Tree of Wisdom to at least 100 feet
Defeat your first Gargantuar
Bowl a winner with a friend in Co-Op Wall-Nut Bowling
Survive 40 waves of pure zombie ferocity
Plant your first 10 peashooters
Go on a 5 game winning streak in VS. mode
Blast 10 zombies at once with a Cherry Bomb!
Win any level after all 5 lawnmowers have been used
Go trunk diving and spend at least $25,000 on Crazy Dave's Twiddydinkies
Stop the horde using only the Sunflower, Wallnut, and Chomper on any level