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.
Play the game after a week long break.
Release all of the names to the sky.
Beyond all flowers lies another room.
Journey to the city unscathed.
Light a darkened pool.
Life could be simple...
Play with the windmills and ride the wind seven times.
Use the grass as your canvas and paint the ground with three different colors.
The dream has just started...
Take a ten minute break between any dreams.
Reminisce for three minutes before returning to the room.
Completely awaken the city.
Find and bloom a secret flower.