Here is the full list of all 18 Strange Horticulture achievements. It takes around 8-10 hours to unlock all of the achievements on Windows.
Bring about the Redemption
Take control of the Servant
Complete a full playthrough without using the hint button
Perform the ritual
Recover from Rising Dread
Murder Burbidge
Identify all the plants
Complete the game
Save the Sisterhood
Create an Elixir
Open the secret drawer
Activate the viewing device
Find a Bryer's Disc location
Pet Hellebore 13 times
Visit 20 map locations
Identify 10 plants
Solve your first clue card
Handle your first customer