Usage
Locally, the blue flowers are commonly used as dyes for colouring confectionaries. In particular, it is used in the savoury Nonya bak chang or "rice dumplings" where it adds a tinge of blue to the dumplings. As a dye, it is popular amongst the health conscious who do not appreciate artificial dyes. The dye can also be used as a litmus while the plant itself is useful as a matting. Various parts of the Javanese variety, which has white flowers, are used in traditional medicine. The white version is grown today only for ornamental purposes. In Australia, the Blue Pea is valued as fodder because of its higher protein content. It also serves to increase the nitrogen level of the soil.