Here is the full list of all 22 Water Buddy achievements.
Pull one buddy out of water
Pull five buddies out of the water
Pull ten buddies out of the water
Pull all of your buddies out of the water
Beat the game
Beat the game without the secret power
Get zapped
Beat the game by zapping the plane
Light up the lamp
Beat the game only zapping missiles
Grow all flowers in garden
Grow all flowers around the statue
Get kicked
Anger your first doofus
Get the dog to escape the fence
Feed your buddies
Nemo vir est qui mundum non reddat meliorem
Beat the game without alerting a dog
Grow 500 grass clumps
Open all mailboxes
Spin the bottle 10 times
Spin a bird bath