Common name: Cup plant
Silphium perfoliatum is a flowering perennial plant native to central and eastern North America. It sports small, yellow flowers in mid-summer, which look like sunflowers, on tall stems, 1-2.5 m (3-8 ft) high. The leaves are large and coarse. They grow opposite each other and form a cup shape. Our sole specimen is in the Alma Van Dusen Garden across from the delphiniums and needs to be supported by a bamboo frame.
Flower photo in the public domain via Wikimedia
Plant photo by Tresa Horney