Medicinal plants have been used for centuries before the advent of orthodox medicine. Leaves, flowers, stems, roots, seeds, fruit, and bark can all be constituents of herbal medicines. The medicinal values of these plants lie in their component phytochemicals, which produce definite physiological actions on the human body. It is a vigorously growing and twining annual plant and has a number of species and hybrids. The trailing vines and leaves are grown mostly for green manuring or temporary pasture.