Slender Rosinweed (Silphium Gracile)
Slender Rosinweed
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 genus name Silphium comes from the Greek name silphion, used to refer to a resin-bearing plant from northern Africa.
Specific epithet means slender.
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.
| Hardiness zone | 5 - 9 |
| Sun light | Full Sun To Part Shade |
| Water | Medium |
| Maintenance | Low |
No serious insect or disease problems.
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.
| Common name | Slender Rosinweed |
| Botanical name | Silphium Gracile |
| Plant type | Herbaceous Perennial |
| Family | Asteraceae |
| Hardiness zone | 5 - 9 |
| Water | Medium |
| Maintenance | Low |
| Flower color | Yellow |
| Flowering period | September - Oc- Ber |
| Height | 4 - 6 Ft. |
| Width | 1 - 2 Ft. |