Khurasani Ajwain – Uses, Benefits and Dosage Description of Plant Parasika Yavani (Hyoscyamus niger) is an erect viscidly hairy, annual herb having nauseous odor growing 30-150 cm high. There are two forms of the plant, an annual and a biennial. The annual grows during the summer to a height of 30 to 60 cm (1 to 2 feet) and then flowers and sets seed. Biennial produces only a tuft of basal leaves during the first season, which get disappear in