Cytisus scoparius
Common name: 
Scotch Broom
Common Broom
SI-ti-sus sko-PAH-ree-us
Native to (or naturalized in) Oregon: 
  • Broadleaf deciduous shrub, 4-8 ft (1.2-2.4 m), dense, rounded mound, slender green branches.   Leaves alternate, compound, 3-leaflets, each about 13 × 6 mm, obovate or lanceolate.  Flowers sweet-pea shaped, bright yellow, about 2.5 cm long, solitary or in pairs, can cover the plant in spring and early summer, very noticeable.  Fruit a pod, 4-5 cm long, hairy along the margin, green, finally brown.
  • Sun.  Drought resistant.
  • Hardy to USDA Zone (5) 6      Native to central and southern Europe.
  • Caution:  This species is often considered an invasive shrub-weed, it establishes in abandoned areas and is very competitive since it is a nitrogen fixer.   In February 2010, the Oregon Department of Agriculture amended its noxious weed quarantine (OAR 603-52-1200) to include Cytisus scoparius and the rule "prohibits the growing or sale of Scotch broom in Oregon regardless of the variety or cultivar.  C. scoparius should not be grown or sold in Oregon."
  • There are cultivars that are thought to be less aggressive than the species, but supporting data is minimal.   Flowers colors range from white ('San Francisco'), pale yellow ('Moonlight'), lilac-pink ('Lilac Time'), orange and apricot ('Pomona'), to red ('Stanford').
  • Oregon State Univ. campus: southwest Reser Stadium (probably a cultivar).
Click image to enlarge
  • plant habit, flowering, naturalized site

    plant habit, flowering, naturalized site

  • single plant, flowering

    single plant, flowering

  • shoots with flower buds

    shoots with flower buds

  • flowers


  • flowers and fruit

    flowers and fruit

  • plant habit, after flowering

    plant habit, after flowering

  • branches and fruit

    branches and fruit

  • plant habit, single plant at seed release

    plant habit, single plant at seed release

  • fruit at seed release

    fruit at seed release