Overview of Brown-eyed Susan

Rudbeckia triloba is an herbaceous biennial or short-lived perennial with many common names including branched coneflower, thin-leaved coneflower, three lobed coneflower and brown-eyed Susan. It is native to the prairies of the eastern and Midwestern US (New York to Florida, west to Minnesota, Utah and Texas), and is naturalized in open woods and old fields, and on rocky slopes. Brown-eyed Susan is hardy in zones 4a-8b.

The name “triloba” comes from the dark green, somewhat hairy basal leaves that are divided into three oval parts. This plant is similar to the very common black-eyed Susan (R. hirta), but is taller, flowers later and over a longer period of time and has much smaller flowers.

Masses of yellow daisies with brown centers make this a late-season garden standout. Plants burst into bloom in late summer through fall, or until a hard frost.

Plants produce abundant small (1-2″ across), flat, brilliant yellow flowers with button-shaped jet-black centers that fade to brown. The 8-10 ray flowers are proportionally shorter and wider than those of other coneflowers.

Flowers are produced at the ends of many-branched, erect stems with narrow leaves, so the plants are completely covered with blooms. R. triloba grows 2-5 feet tall and 1-1.5 feet wide.