Cup Plant
Silphium perfoliatum
Asteraceae
Growth habit
Herbaceous
Native distribution
Ontario to SD, South to GA, Ms and OK
Location
Source of plant
The Plantsmen
Description
A robust perennial reaching 2.5m in height with several glabrous stems held erect in a massive clump from a woody rotstock, sharply 4-angled, branched only towards the top; leaves opposite, simple, connate-perfoliate, triangular to ovate-acute, to 35cm long, rough on both sides, irregularly scabrous-toothed; inflorescence dichotomous, long-petioled with many 8cm wide, yellow flower heads effective from July to September.
USDA Hardiness Zone
3