Overview
Silphium terebinthinaceum is a perennial herb in the genus Silphium, part of the Asteraceae family. It typically grows around 1.5 m tall. Silphium terebinthinaceum grows best in full sun, and tolerates most soils. Its UK hardiness is rated H7. It is native to E North America.
About
Silphium terebinthinaceum is a perennial herb in the Asteraceae that typically reaches about 1.5 m. It prefers full sun and performs in sandy, loamy or clay soils that are moist but well-drained. Flowering occurs July to September and the foliage is fragrant. Plant where its height can be accommodated towards the back of a border or in open, sunny planting schemes.
Wikipedia contributors, CC BY-SA 4.0 — Silphium terebinthinaceum
About the genus
Silphium is an unidentified plant that was used in classical antiquity as a seasoning, perfume, aphrodisiac, and medicine.
Wikipedia contributors, "Silphium", CC BY-SA 4.0 — Silphium
In the garden
Silphium terebinthinaceum is a perennial herb in the sunflower family native to eastern North America. Plants reach roughly 1.5 m and carry a summer display, with flowering from July to September. The foliage has a noticeable scent, which can be appreciated close to the plant. Give prairie burdock a sunny, open site; it requires full sun and will grow in a wide range of soils from sandy through loam to clay, provided the ground is moist but well-drained. Its UK hardiness is H7, meaning it is fully hardy outdoors across the British Isles; the equivalent USDA range is zones 4–8. Positioning should allow for its mature height and for good air movement around the stems. In UK gardens it suits sunny back borders, prairie-style or meadow planting and any situation where a tall, upright perennial is useful for vertical structure. Group plants so their height is balanced by lower neighbours in front. The scented foliage is a practical feature: place specimens where people will pass nearby to notice the scent during the flowering months.
Growing conditions
Best soil and position for Silphium
- Sunlight
- Full sun
- Soil type
- Sandy, Loamy, Clay
- Soil moisture
- Moist but well-drained
- Exposure
- Full sun
- UK hardiness
- H7
Plant details
Silphium terebinthinaceum size, habit and characteristics
- Plant type
- Perennial herb
- Height
- 1.5 m
- Native to
- E North America
- Fragrance
- Foliage
Care notes
Pruning and caring for Silphium terebinthinaceum
- Propagation
- Seed
Frequently asked questions
Where is the best place to plant Silphium terebinthinaceum?
Silphium terebinthinaceum prefers full sun. It suits full sun positions.
What soil does Silphium terebinthinaceum need?
Silphium terebinthinaceum is adaptable and grows happily in most soil types, including sandy, loamy and clay. Aim for soil that stays moist but well-drained.
How big does Silphium terebinthinaceum grow?
Silphium terebinthinaceum reaches a height of 1.5 m.
Is Silphium terebinthinaceum hardy in the UK?
Silphium terebinthinaceum has an RHS hardiness rating of H7, meaning it is fully hardy throughout the UK, tolerating temperatures below -20°C.
How do I propagate Silphium terebinthinaceum?
Seed.
