Aroma, IndianaAroma is an unincorporated community in White River Township, Hamilton County, Indiana.HistoryAroma, founded in 1836, was named by William P. Haworth, who kept a small store there. Aroma was a descriptive name, perhaps for the scent of fresh-cut hay. A post office was established at Aroma in 1870, and remained in operation until it was discontinued in 1902.