Black-eyed Susan (Rudbeckia hirta)


Black-eyed Susan (Rudbeckia hirta)

Black-eyed Susan (Rudbeckia hirta) also called the Black-eyed Cornflower is a biennial forb/herb in the Aster Family (Asteraceae) and order Asterales. The genus name is honoring the Swedish farther and son who were professors of botany in the seventeenth and eighteenth centuries, O. J. and O. O. Rudbeck. The species name is from the Latin for "hairy."

This plant grows to about 40 inches (one meter) tall. The 2 to 3 inch (5 to 7.5 centimeters) flower heads consists of 8 to 21 yellow ray flowers surrounding dark-brown, domed disk flowers. It blooms from June to September in the second year.

The leaves are 2 to 7 inches (5 to 17.5 centimeters) long, alternate, entire, lance-shaped to ovate, hairy, and with prominent veins. The stems are stout and hairy.

The fruit is a tiny, black, dry, four-angled seed. There are 1,746,000 seeds per pound (0.45 kilograms).

The root system is simple.

The Black-eyed Susan is an excellent plant for erosion control. It is nontoxic and cultivated. One cultivated version has orange ray flowers. This orange variety may escape into the wild. Black-eyed Susans tend to be hardy and prolific.


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