Definition: Petrosia is a genus of flowering plants in the family Asteraceae. It belongs to the order Asterales and is one of the most widely cultivated species. The genus contains over 1,000 species, with many being cultivated for their flowers or their edible fruits. Some common names include petalwort, petalwort, and petalwort, which are derived from Latin roots "petalium" (which means flower) and "wort," meaning herb.