Rudbeckia hirta. At 30–100 cm (12–39") tall, this North American native annual wildflower is immediately familiar, and conjures a sense of the heat of mid-summer. Dark brown cone centres are surrounded by pure yellow petals in flowers 5-8cm (2-3") across. Black Eyed Susan is a common name shared by many plants, but this is the annual that is native to the northeastern United States. This plant has been used by a number of First Nations as a medicinal poultice to treat a number of infections, including cold and flu. You'll love the bright look of this plant in mass plantings or in larger containers.