Rehmannia

Rehmannia glutinosa
A rhizomatous perennial, reaching up to 16 inches tall, that is native from central to northeast China as well as Japan.
The toothed, ovate leaves are up to 5 x 2.5 inches in size. The foliage is soft hairy.
The orange ( veined purple ) flowers, up to 1.8 inches long, appear mid to late spring.
Hardy zones 5 to 8 in full sun to partial shade on moderately moist, fertile, well drained soil.