Cup Plant is a fascinating and vigorous giant that offers a unique ecological service by providing a natural watering station for local wildlife. Its common name is derived from the way its large, opposite leaves fuse together around the square stem to form a distinct 'cup' that collects and holds rainwater. These miniature pools are frequently visited by thirsty birds, beneficial insects, and even small tree frogs during the heat of summer. Reaching heights of four to eight feet (and sometimes taller in moist soils), the plant produces a prolific display of yellow blooms from July through September. Native to moist prairies and stream banks across central and eastern North America, it thrives in full to partial sun and prefers medium to moist soils. Due to its aggressive, rhizomatous growth habit, it is best suited for larger spaces where it can spread freely to create a dense, wildlife-friendly screen. It is an ecological powerhouse, supporting a vast range of pollinators and providing structural diversity to any wetland or meadow planting.

Quick facts

• Height: 4–8 ft
• Sun: Full to Partial
• Soil moisture: Medium-Wet to Medium
• Bloom time: Jul–Sep (Yellow)
• Life cycle: Perennial
• Notes: Aggressive
• Native range: Native to 31 states, including Iowa, Minnesota, Wisconsin, Illinois, Missouri, Nebraska

See the full growing guide and county range map for Cup Plant