Rehmannia is a perennial plant of the Phrymaceae family also known as the lopseed family.
It is similar in appearance to foxglove (Digitalis purpurea). Its leaves are mostly at ground level and it blooms with flowers that can range from yellow to burgundy in color.
The plant was brought from Asia to the West in the eighteenth century and is cultivated mostly as an ornamental garden plant in the United States and Europe. The whole plant is used to make herbal medicine. It is commonly used in combination with other herbs in Traditional Chinese Medicine and Japanese Medicine.