Gentiana andrewsii
Closed bottle gentian
 
Bottle Gentian is a blue-flowered woodland garden plant that grows to 1-2 feet in height. Unlike most flowers the blossoms of the Bottle Gentian stay closed at the tip, looking almost like an old-fashioned Christmas light. These beauties thrive in moist soils and cool shade, and typically do not flower until the Fall, serving as a later food source for bumblebees.