Species Native to Missouri
Common Name: compass plant
Type: Herbaceous perennial
Family: Asteraceae
Native Range: Central North America
Zone: 3 to 8
Height: 5.00 to 9.00 feet
Spread: 1.50 to 3.00 feet
Bloom Time: July to September
Bloom Description: Yellow
Sun: Full sun
Water: Medium
Maintenance: Low
Flower: Showy
Attracts: Butterflies
Culture
Easily grown in average, medium, well-drained soils in full sun. Tolerates poor soils.
Noteworthy Characteristics
Silphium laciniatum, commonly called compass plant, is a herbaceous perennial native to prairies, glades, roadsides, railroad right-of-ways, and other open, disturbed habitats in the Midwest and portions of the southern United States. A tall, sturdy, rough, bristly plant that grows on stiff, hairy, resinous stems to 9' tall. Features sunflower-like flowers (to 5" wide) with yellow rays and yellow center disks. Flowers bloom in loose spikes on the upper parts of the plant in summer. Very large, deeply pinnatifid (cut close to the midrib) basal leaves (to 18" long) are reminiscent of pin oak leaves. Upper leaves are smaller.
The genus name Silphium comes from the Greek name silphion, used to refer to a resin-bearing plant from northern Africa.
Specific epithet means slashed or torn into narrow segments in reference to the deeply cut leaves.
Problems
No serious insect or disease problems. Slow to establish and may not flower until the second or third year.
Uses
Good height for the rear of the border. Also excellent for naturalizing in prairies, cottage gardens, wildflower gardens or native plant gardens.