Butterfly pea (Clitoria Ternatea)

Butterfly pea is frequently used in Ayurvedic
medicine, as a memory enhancer, antidepressant and tranquilliser. Different
parts of the plant have been shown to have different properties, but an
infusion of the roots appears to be most effective. In traditional Chinese
medicine it was used to treat infertility and ailments of the female
reproductive system. In other traditional medicines it was used to encourage
menstruation.
The flowers are used to colour food, or make
herbal tea that is blue in alkaline solution, turning pink if acids such as
lemon juice are added.

Drawings of Indian plants and trees later named at the Royal Botanical Gardens Kew