Here is the full list of all 14 Flower achievements. It takes around 4-5 hours to unlock all of the achievements on Windows.
Bloom 10,000 flowers.
Journey to the city unscathed.
Use the grass as your canvas and paint the ground with three different colors.
Beyond all flowers lies another room.
Life could be simple...
The dream has just started...
Release all of the names to the sky.
Light a darkened pool.
Completely awaken the city.
Reminisce for three minutes before returning to the room.
Play with the windmills and ride the wind seven times.
Play the game after a week long break.
Take a ten minute break between any dreams.
Find and bloom a secret flower.