Silphium perfoliatum, commonly known as Cup Plant, is a tall and bold North American native perennial with square stems that appear to pierce its large opposite leaves. In summer, it produces bright yellow sunflower like blooms that attract a wide array of pollinators. Its towering stature and unique foliage make it a striking addition to naturalized plantings, prairies, and pollinator gardens.
Height & Spread: 72 - 96 in x 36 - 48 in
Bloom Time: July to September
Light Requirements: Full sun
Soil Preference: Moist, fertile, well drained soils; tolerates clay
Watering Needs: Moderate to high; thrives in moist conditions
Deer Resistance: Deer resistant due to coarse foliage texture
Native Status
Silphium perfoliatum is native to eastern and central North America, thriving in moist meadows, stream banks, and low prairies. It is an excellent choice for native restoration projects and pollinator habitats.
WILDLIFE & INSECTS
Bees
- Provides abundant nectar and pollen for native bumblebees, honeybees, and sweat bees throughout mid to late summer.
Butterflies
- Attracts Monarchs, Swallowtails, and other large butterflies to its nectar rich blooms.
Birds
- Goldfinches and other seed eating birds feed on the ripened seeds in late summer and fall.
Beneficial Insects
- Supports predatory wasps and beetles which help manage pest populations in the garden.
Spacing & Landscape Use
Spacing Recommendations:
- Allow 36 - 48 in spacing to accommodate its large leaves and tall upright growth.
Landscape Placement:
- Ideal for the back of borders, naturalized meadows, rain gardens, and pollinator plantings where its height and unique foliage are featured.
Companion Plants
- Schizachyrium scoparium (Little Bluestem) - Adds graceful blue green foliage and warm fall tones beneath the tall Cup Plant.
- Vernonia noveboracensis (New York Ironweed) - Tall deep purple flowers offer a striking contrast to the yellow blooms of Cup Plant.
- Rudbeckia laciniata (Cutleaf Coneflower) - Produces large yellow blooms that blend naturally with Silphium in prairie style plantings.
- Asclepias incarnata (Swamp Milkweed) - Pink summer blooms attract Monarchs and pair well with moist loving Silphium.
- Eupatorium maculatum (Joe Pye Weed) - Provides pink to mauve umbels that complement the structure and attract similar pollinators.