Silphium terebinthinaceum

RHS Plant Profile
prairie burdock
prairie burdock RHS

Other common names

prairie rosinweed, turpentine, turpentine weed, prairie dock

Herbaceous Perennial

A very tall herbaceous perennial, to 4m, with a basal rosette of very large, oblong to heart-shaped leaves. Sturdy, upright, branching stems support masses of yellow, daisy-like flowers from mid-summer to mid-autumn

Position

Full sun, Partial shade

Soil Types

Clay, Loam

Max Height

2.5-4 metres

Max Spread

0.5-1 metres

Size

Time to Maturity
2–5 years
Max Spread
0.5-1 metres
Max Height
2.5-4 metres

Growing Conditions

Clay Loam
Moisture
Moist but well–drained or Well–drained
pH
Alkaline or Neutral

Position

Full sun Partial shade
Aspect
South–facing or West–facing or East–facing
Exposure
Exposed or Sheltered
Hardiness
H7

Colour & Scent

Fragrance Foliage
Season Stem Flower Foliage Fruit
Spring
Summer
Autumn
Winter

Botanical Details

Family
Asteraceae
Native to GB/Ireland
No
Foliage
Deciduous
Habit
Bushy
Genus
Silphium are robust herbaceous perennials with tall stems bearing simple leaves, aromatic when bruised, and loose clusters of yellow, daisy-like flowers in summer and early autumn
Name Status
Correct
Plant Range
E North America

How to Grow

Cultivation

Grow in moist, deep, neutral to slightly alkaline soil in full sun or partial shade; best in heavy soil

Propagation

Propagate by seed or division

Suggested planting locations and garden types

  • Cottage and informal garden
  • Architectural
  • Prairie planting
  • Flower borders and beds

Pruning

May be cut back after flowering, or leave architectural stems until shortly before new growth begins the following season

Pests

Generally pest-free

Diseases

Generally disease-free