Here is the full list of all 20 Platform Golf achievements.
Reach level 10.
Collect 8 Coins in 1 Level
Collect 2 gems in 1 Level
Hit the top of any level
Finish a level with 8 hits left.
Collect 100 Coins in one Play session
Collect 20 gems in one play session
Hit any mushroom 5 times in one level
Finish a level with 0 hits left
Hit a Tree 5 Times in one Level
Watch the credits
Fall into the water
Finish any Level with one shot
Finish any level in under 12 seconds
Get to Level 21
Reach Level 30
Reach level 42
Clear all levels in the forest
Get a highscore over 2500
Get every Achievement.