Cup Plant, Silphium perfoliatum
Cup Plant is a bold and stately native perennial with dramatic sunflower-like yellow blooms that span 2-3 inches across. This impressive plant is distinguished by its unique square stems and pairs of large opposite leaves that join around the stem, forming distinctive water-filled "cups" that collect rainwater. These natural reservoirs provide drinking water for small birds, insects, and pollinators, making it a one-stop café for backyard wildlife. The plant blooms from mid to late summer with weeks of brilliant yellow flowers atop 1.2-2.4 meter tall stems.
Ecology:
One of the best native perennials for wildlife support, Cup Plant attracts an incredible diversity of pollinators including Eastern Tiger Swallowtail butterflies, native bees, bumble bees, honey bees, wasps, and hummingbirds. Goldfinches feast on the seeds, and small birds drink from the leaf cups. The stems can be used to make mason bee homes after the plant dies back in winter. A tremendous pollinator plant that supports specialist bees, moths, and creates a true pollinator park in your garden.
Growing conditions:
Cup Plant thrives in full sun to partial shade and prefers moist, deep soil, naturally found in low woods, prairies, meadows, and along streams. Once established (3+ years), the long taproot makes it very drought and heat tolerant. Hardy in zones 3-9, it tolerates clay or wet soils. Spreads by rhizomes and self-seeds. This gentle giant naturalizes well in prairie gardens, wildflower gardens, and along water features.