Blue Berries

Blue berries can be found by first locating a blueberry bush growing in the Forest and Jungle biomes (more commonly found in the Forest Biome). Using a Pickaxe to harvest the bush will leave you with blue berries. Blue berries are used to craft Blue Dye at a Dye Vat and placing them will cause a blueberry bush to grow, similarly to the function of acorns in growing trees.