Here is the full list of all 19 Bloom: Roots of Renewal achievements.
Kill 20 Poisonous Plants
Kill 50 enemies with the Machine Gun
Complete The Ruins in less than 6 minutes
Kill 400 Enemies
Kill 1,000 Enemies
Kill 20 Spiders
Pick Up A Weapon
Complete The Ruins
Complete The Village
Complete The Archives
Obtain a score of 22500 on The Ruins
Kill 25 Ents
Kill 100 Enemies
Complete The Ruins only using the single shot
Kill every enemy in a given level
Collect Every Book
Kill 3 enemies with one Triple Shot
Kill an enemy at least 50m away with the sniper
Kill a flying enemy while in the air