Annuals Dictionary: Rudbeckia
Daisy family
Compositae
Rood-beck’i-a. Coneflower . North American hardy herbs, comprising about 25 species.
Description
Leaves usually alternate, simple or compound, in some species much cut and lance-shaped, veins prominent, margins deeply toothed toward the tip. Flowers in terminal or axillary heads, generally yellow, in most species the disk flowers being brown or black.
How to Grow
Easy to grow. Sow outdoors in warm soil. Where growing season is short, start seeds indoors 8-10 weeks before last spring frost. Seedlings transplant easily. Plants grow rather large and should be set 18 in. (45 cm) apart. They prefer warm weather.
Rudbeckia hirta
Black-eyed Susan . 1-3 ft. (30-90 cm) high, covered with short stiff hairs. Flowers daisylike, 2-3 in. (5.0-7.5 cm) wide, ray flowers yellow, disk flowers purplish brown. Originally restricted to the Midwest, now naturalized from s. Canada to n. Mexico. Many desirable cultivars have been created by hybridizing R. hirta and by breeding for tetraploid forms such as the ‘Gloriosa Daisy’ below. In the process, a rough-looking wildflower has become a mainstay in summer gardens. Very resistant to heat and drought. Short-lived perennial grown as a half-hardy annual.
Rudbeckia hirta ‘Gloriosa Daisy’
2-3 ft. (60-90 cm) high. Flowers to 6 in. (15 cm) wide, from yellow and gold to mahogany, red, or bicolored. Some with double or semidouble blossoms. Short-lived perennial grown as a half-hardy annual.