Cup plant, Silphium perfoliatum, is a beautiful native Ontario plant. Its large stature, (6 to 9 feet tall), and wide, tapered leaves are further complemented by an abundance of open yellow flowers. The flowers will re-bloom well into the autumn. A large plant that needs lots of space. Some gardeners find it to be an effective...
Botanical Name: Silphium perfoliatum
Nom Français: Silphie perfoliée
Bloom colour: Yellow
Blooms: Fall - Zone 5 | Summer - Zone 5
Pollinators: Birds | Butterflies | Hummingbird
Sun or Shade: Full Sun
Plant Type: Perennial
Height: Up to 9+ feet (3.5 meters)
It grows well in hardiness zones: 3 to 9
Prairies and meadows
Water requirement: Dry to Moist
Easily grown in average, medium to wet soils in full sun; tolerates some drought once established. Somewhat slow to establish when grown from seed. Self-seeds in optimum growing conditions.
Spread: Up to 90 cm
Native to Canada
Styling and Use
Try it with Aster, Hibiscus, Monarda fistulosa or Panicum virgatum
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