Vacha, commonly known as Sweet Flag, is a semi-aquatic, perennial, aromatic herb with creeping rhizomes belonging to the family Acoraceae. The plant is found in the northern temperate and subtropical regions of Asia, North America and Europe. The leaves are closely arranged sword-like in structure, radiant green in color, thicker in the middle and have curvy margins. The rhizome is vertically compressed, spongy, pale to dark brown or occasionally orange brown in color. Studies have shown that Vacha has significant action on the central nervous system such as anticonvulsant, sedative, hypnotic, tranquilizing, and memory enhancing. Hence it is used for treatment of diseases like schizophrenia, epilepsy, neuralgia. The rhizomes of Vacha also possess aromatic, stimulant, bitter tonic, emetic, expectorant, emmenagogue, aphrodisiac, laxative, diuretic, antispasmodic, carminative, and anthelmintic properties. 
Ayurvedic significance:
	
Rasa (taste): Katu, Tikta (Pungent, bitter)
	
Veerya (nature):Ushna (Hot)
	
Vipaka (taste developed through digestion): Katu (Pungent)
	
Guna (qualities):Laghu, Tikshna (Light, Sharp)
	
Doshas (effect on humors): Balances Vata & Kapha