Here is the full list of all 19 Highway Blossoms achievements. It takes around 15-20 hours to unlock all of the achievements on Windows.
Checked out the credits on your own time
Completed Highway Blossoms on Extreme difficulty
Let's hope you don't ever again
Turned on Goofball Mode
You know what you did
Checked out the guest art section. Now all it needs is a glass case.
Finished the epilogue
Finished the story
Got lucky at blackjack
Unlocked every journal entry
Now you're back on track
Didn't find the second piece of treasure
Found the first piece of treasure
Got a copy of the miner's journal
Started a new game
Tried out the hi-contrast textbox. Who knows, you might like it!
Turned on skip mode for all messages
Set the character speed below 10 characters per second