Easily grown in average, medium to wet soils in full sun. Prefers moist, rich soils, but tolerates some drought once established. Somewhat slow to establish when grown from seed. Self-seeds in optimum growing conditions.
Silphium perfoliatum, commonly called cup plant, is a coarse, sunflower-like, Occurs in low woods and thickets, meadows, prairie stream/pond peripheries and along railroad tracks. It typically grows on tough, erect stems to 4-8' tall and is distinguished from the other silphiums by its square/quadrangular stems and pairs of cup-forming leaves. Flower heads (to 3" diameter) featuring light yellow rays (20-40) and darker yellow center disks bloom in summer on the upper part of the plant. Rough, triangular to ovate, coarsely-toothed, opposite, connate-perfoliate, medium green leaves. Lower leaves (to 14" long) are united at the petioles. Middle and upper leaves lack petioles, and leaf pairs are united at the bases to envelop the stem forming a cup (hence the common name). Leaf cups will collect rain water. This species is also commonly called cup rosin weed because its stems (like those of all silphiums) exude a gummy sap when broken or cut.)
No serious insect or disease problems.
A large plant that needs lots of space. Some gardeners find cup plant to be too large and weedy for border rears, but others find it to be an effective backdrop for other perennials. Adapts well to prairies, wildflower/native plant gardens, naturalized areas or moist, open woodland areas including stream/pond edges.