Family: Asteraceae (ass-ter-AY-see-ee) (Info)
Genus: Silphium (SIL-phee-um) (Info)
Species: pinnatifidum (pin-nat-ih-FY-dum) (Info)
Synonym:Silphium chickamaugense
Synonym:Silphium terebinthinaceum var. pinnatifidum
 One vendor has this plant for sale.
Category:
Perennials
Height:
18-24 in. (45-60 cm)
Spacing:
12-15 in. (30-38 cm)
15-18 in. (38-45 cm)
18-24 in. (45-60 cm)
24-36 in. (60-90 cm)
Hardiness:
USDA Zone 4b: to -31.6 °C (-25 °F)
USDA Zone 5a: to -28.8 °C (-20 °F)
USDA Zone 5b: to -26.1 °C (-15 °F)
USDA Zone 6a: to -23.3 °C (-10 °F)
USDA Zone 6b: to -20.5 °C (-5 °F)
USDA Zone 7a: to -17.7 °C (0 °F)
USDA Zone 7b: to -14.9 °C (5 °F)
USDA Zone 8a: to -12.2 °C (10 °F)
USDA Zone 8b: to -9.4 °C (15 °F)
USDA Zone 9a: to -6.6 °C (20 °F)
USDA Zone 9b: to -3.8 °C (25 °F)
USDA Zone 10a: to -1.1 °C (30 °F)
USDA Zone 10b: to 1.7 °C (35 °F)
Sun Exposure:
Full Sun
Danger:
N/A
Bloom Color:
Bright Yellow
Bloom Time:
Mid Spring
Foliage:
Herbaceous
Blue-Green
Other details:
This plant is attractive to bees, butterflies and/or birds
Average Water Needs; Water regularly; do not overwater
Self-sows freely; deadhead if you do not want volunteer seedlings next season
Soil pH requirements:
6.1 to 6.5 (mildly acidic)
6.6 to 7.5 (neutral)
7.6 to 7.8 (mildly alkaline)
Patent Information:
Non-patented
Propagation Methods:
From seed; direct sow outdoors in fall
Seed Collecting:
Allow seedheads to dry on plants; remove and collect seeds
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