Aak, Madar (Calotropis gigantea) – Uses, Benefits, Dosage and Properties Arka (Calotropis gigantea) is a perennial shrub growing 2.5 meter high with various branches and sub branches. Leaves are simple, opposite, sub sessile, ovate and cordate at base. It has bunch of waxy flowers that are white or lavender in color. Flowers consists of pointed five petals and a small beautiful crown, which holds the stamen. It has milky stem and contains cardiac glycosides, fatty acid and calcium oxalate. General