Silphium Cup Plant Seeds (Silphium Perfoliatum) 15+Seeds
Silphium (Silphium Perfoliatum) - This towering, flowering plant is a native of the tall grass prairie and readily establishes from Silphium seeds. It is commonly known as Cup Plant and is a perennial giant which has yellow daisy-like flowers. The flowers measure 3 - 4 inches across and attract bees and birds. The name comes from the large leaves that are on opposite sides of the stem and are fused together at their base. This base forms a cup that collects water from the morning dew. Birds and insects seek out the collected water.
The Silphium Cup Plant prefers sunny settings and moist loamy soil. The root system consists of a long central tap root and many shallow rhizomes. The rhizomes help to spread the plant. The Silphium Perfoliatum Cup Plant will often form substantial colonies due to the spreading ability. How To Grow Silphium: Sow Silphium Perfoliatum seeds directly outdoors in late fall or early winter. These particular flower seeds do well with a cold, dormant planting as the cold temperatures actually help break the flower seed of its dormancy. Once spring arrives and temperatures warm, the Cup Plant seeds will germinate quickly. Prepare the outdoor soil by removing weeds and loosening. Silphium Cup Plant seed can be raked into loosened soil and covered 1/8 - 1/4 inch.
- Season: Perennial
- USDA Zones: 4 - 9
- Height: 40 - 90 inches
- Bloom Season: Late spring through summer
- Bloom Color: Yellow
- Environment: Full sun