Silphium integrifolium (Rosin Weed)
Silphium integrifolium (Rosin Weed)
170 (250)cm, Rosin Weed is a tall and showy herbaceous perennial with large, smoothly haired, entire leaves on a purplish stem with terminal lose racemes of bright sulfur yellow flowers. It is native of rocky and dry open woods in central USA. Easily grown in a rich, well drained soil in a preferably sunny spot. VII-IX.More Details »