Silphium gracile

Common Name: slender rosinweed 
Type: Herbaceous perennial
Family: Asteraceae
Native Range: Southeastern United States
Zone: 5 to 9
Height: 4.00 to 6.00 feet
Spread: 1.00 to 2.00 feet
Bloom Time: September to October
Bloom Description: Yellow
Sun: Full sun to part shade
Water: Medium
Maintenance: Low
Flower: Showy
Attracts: Birds, Butterflies

Culture

Easily grown in average, medium moisture, well-drained soils in full sun to part shade. Tolerates some drought once established. Plants may be cut back in early summer to reduce mature plant height. Plants may be slow to establish in the garden, particularly when grown from seed. Self-seeds in optimum growing conditions.

Noteworthy Characteristics

Silphium gracile, commonly called slender rosinweed, is a coarse, sunflower-like perennial that is native from Texas to Florida. It typically grows to 4-6’ tall on rough, erect stems sparsely clad with oval leaves. Individual plants often display a spindly appearance. Flower heads (to 3” diameter) featuring light yellow rays and greenish center disks bloom in late summer to early autumn on the upper part of the plant. The common name of rosinweed is in reference to the fact that the stems (like those of all silphiums) exude a gummy sap when broken or cut.

The genus name Silphium comes from the Greek name silphion, used to refer to a North African resin bearing plant.

Specific epithet means slender.

Problems

No serious insect or disease problems.

Garden Uses

A large plant that needs lots of space. It is best planted in groups. Some gardeners find it to be too large and weedy for border rears, but others find it to be an effective backdrop for other perennials. Adapts well to prairies, wildflower/native plant gardens, naturalized areas or moist, open woodland areas.