Here is the full list of all 18 Grow Up achievements. It takes around 8-10 hours to unlock all of the achievements on Windows.
Discover the bull and the sheep
Complete all challenges
Complete the game 100%
Plant 10 Champolines on top of each other
Bounce on a Youch 7 times without touching the ground
Complete a challenge holding a Critter
Take a Critter to the moon
Blast a Critter 100m
Ride two Sporchids simultaneously for 400m
Throw 100 seeds whilst gliding
Orbit the entire planet in BALL mode
Collect all crystals
Unlock all Telerouters
Flower all STARPLANTS
Discover letter block P
Rescue MOM
Unlock all seeds
Visit all biomes