Silphium perfoliatum, the cup plant, cup-plant or compass plant, is a species of flowering plant native to eastern and central North America. It is an erect herbaceous perennial with triangular toothed leaves, and daisy-like yellow flower heads in summer.

The typical height of S. perfoliatum plant ranges from 1-2.5 m (3-8 ft). The first flower develops on the tip of the main stem, then many more flowers develop on side branches.

The flowers, which appear from midsummer to autumn (fall), look very similar to sunflowers, but smaller.

Silphium perfoliatum is able to establish colonies due to its central taproot system and shallow rhizomes. S. perfoliatum has an extensive root system and does not transplant well except when very young.

Type: Hardy perennial

Height: 4-8

Height: 6'8", 200 cm

Location: Sun

Seeds per packet: 20