Dog Fennel

Eupatorium capillifolium


Location in our garden

Section A (Principal)


Shrubs. An herbaceous perennial weed, reaching over1.6 m in height.

Part Used

  • Leaves

Growing Requirements

  • Full Sunshine
  • Drought Resistant


  • Roadside
  • Grassland


Native to North America, Eupatorium capillifolium. The name of the genus is derives from the Greek name for these herbaceous and shrubby plants in honor of the King of Pontus, Mithridates VI Eupator, 132-63 B.C., who allegedly found medicinal uses for some plants of the species Eupatorium.

Vernacular Names

Hinojo de sabana (Spanish), Sneeze weed (English).


In pastures, roadsides, abandoned fields, and waste areas, it is a common weed. Dog fennel favors places that receive full light, but can be found in partial shade areas. In damp but well-drained soils, it is readily cultivated. Best in hot summer climates with some afternoon shade. Tolerates most forms of soil. Tolerates dry soils that are sandy. Plants have high tolerance to drought.


  • Roots - fibrous root.
  • Stem - stiff, woody-based, often reddish, upright stems clad with crowded, feathery.
  • Leaves - finely-dissected leaves which are pinnately divided into thread-like segments. Leaves are unpleasantly aromatic when crushed.
  • Flowers - minute, greenish-white, somewhat ornamentally insignificant flowers bloom in late summer. The small, 3-5 flowered heads are numerous and arranged in large, leafy, pyramid-shaped end clusters (corymbs).
  • Fruits - smooth achenes.

Chemical Constituents

  • The essential oil from the aerial parts of E. capillifolium contained cymene (23.7%), selin-11-en-4α-ol (12.3%), methyl thymol (8.9%), and β-bisabolene (8.24%) as the major constituents.

Traditional Medicinal Uses

  • There are essential anti-inflammatory, antifungal and insecticidal activities in this plant. Eupatorium purpureum has been mainly used to treat urinary tract infections and inflammation and as a diuretic.
  • Native Americans used infusions for the treatment of fever, cold, pneumonia, arthritic and rheumatic pains.


  • Dog fennel can be propagated by seeds(generative propagation) and spreading rootstocks (vegetative propagation).
  • Removal of individual plants will prove difficult because of its fibrous root system, and care must be taken to make sure that all roots are removed to avoid re-sprouting. Hand-removal of seedlings is successful before the creation of an extensive root system.

Snapshot of Part Used

Reference Sources

  1. CABI. (2020). Eupatorium capillifolium (Dog fennel) 26-10-2020.
  2. Home & Garden Information Centre. (2020).DOGFENNEL. 26-10-2020.
  3. Misssouri Botanical Garden. (No date). Eupatorium capillifolium. 26-10-2020.
  4. Tabanca, N., Bernier, U., Tsikolia, M. (2010). Eupatorium capillifolium Essential Oil: Chemical Composition, Antifungal Activity, and Insecticidal Activity. 26-10-2020.