Virginia ecotype
- Duration: Perennial
- Habit: Upright, deep rooted
- Size: Foliage typically 2-3 feet tall/wide; its flowering stalks can reach up to 8 feet tall when in bloom
- Flowering Time: July to September
- Bloom Color: Lemon-yellow to gold with dark centers
- Habitat: Sandy sites, dry pinelands and grasslands
- Moisture: Dry to average, must be well draining
- Light: Full sun to part sun; adapted well to part-sun
- Soils: Tolerant of all soil types so long as dry and well draining
- Uses: Low-growing pollinator gardens, dry meadow plantings, cottage gardens, woodland gardens
- Grower's Note: this deep rooted perennial should not be transplanted one to two years after planting
Silphium compositum (Kidney-leaf rosinweed)
Silphium compositum is known (bizarrely) as the kidney-leaf rosinweed. Maybe "kidney" refers to the large deep-red veins on the beautifully lobed leaves of this rosinweed, or maybe they're kidney-shaped if you squint your eyes; we aren't sure! What we do know is it is a very unique and beautiful native that's rarely offered in cultivation.
Kidney-leaf rosinweed is a fire-adapted and deeply rooted perennial of the Silphium genus, often found in woodlands, prairies, glades, and dry, sunny slopes. Its large rough basal leaves are reminiscent of swiss chard, and not palatable to herbivores like deer. One would think this Silphium prefers full sun, but it is perfectly adapted to part sun as well, such as those sites found along woodland edges and openings in canopies.
Adapted to lean, sandy, or well-drained soils where some other perennials may not thrive, this species is notably drought tolerant and develops a deep root system that helps it persist through challenging conditions. As such it needs to be planted in well-draining soil and not be transplanted after established. Its foliage stays low to the ground, and is easy for other taller perennials to overshadow, so plant it with shorter species.
From summer to early fall Silphium compositum sends up flower stalks from its basal rosette. The flowering stems may reach 8 feet tall, producing branches of lemon-yellow to buttery gold blooms. The flowers are attractive to many pollinators, and its large sunflower like seeds are picked and eaten by goldfinches.