Butterfly pea flower 101
It is a perennial herbaceous plant, with elliptic, obtuse leaves. It grows as a vine or creeper, doing well in moist, neutral soil. Its most striking feature is the color of its flowers, a vivid deep blue; solitary, with light yellow markings. They are about 4 cm (1+1?2 in) long by 3 cm (1+1?4 in) wide. Some varieties yield white flowers. The fruits are 5–7 cm (2–2+3?4 in) long, flat pods with six to ten seeds in each pod. They are edible when tender. It is grown as an ornamental plant and as a revegetation species (e.g., in coal mines in Australia), requiring little care when cultivated. As a legume, its roots form a symbiotic association with soil bacteria known as rhizobia, which transform atmospheric N2 into a plant-usable form (a process called nitrogen fixing), therefore, this plant is also used to improve soil quality through the decomposition of nitrogen rich plant material.