Poncirus trifoliata
Common name: 
Trifoliate Orange
Hardy Orange
Bitter Orange
pon-SEER-us try-foh-lee-AY-tuh
Native to (or naturalized in) Oregon: 
  • Deciduous shrub or small tree, 8-20 ft (2.4-6 m) tall and about 5-15 ft (1.5-4.5 m) wide, stems green, glabrous, with stout spines, 1-4 cm, and occasionally 7 cm long.  Leaves alternate, compound, 3-foliate, terminal leaflet obovate to elliptic, 2.5-6 cm long, apex obtuse or emarginate, base wedge-shaped, dark green, lateral leaflets similar but smaller; petiole 8-20 mm long, often winged.  Flowers white, solitary, fragrant, axillary, 5 petals, 3.5-5 cm across, 8-10 stamens, appear before or with leaves.  Fruit globose, 3.5-5 cm across, green then yellow, very sour, contains numerous seeds.
  • Sun, shelter from cold winds.  Best in fertile well-drained soil.  Frequently grown in a tub, against a sunny wall, or as a spiny hedge, it withstands shearing well.  Because of the thorns, avoid planting near foot traffic areas.  No serious pests or diseases.
  • Hardy to USDA Zone 5    Native to northern China and Korea.  Used as a dwarfing rootstock for citrus.
  • A popular cultivar: 'Flying Dragon'  -  shrub or small tree, twisty stems and spines
  • trifoliata: three leaves (leaflets)
  • Portland, Oregon: Bishop's Close Elk Rock Garden.
Click image to enlarge
  • plant habit, flowering

    plant habit, flowering

  • flowerng branches

    flowerng branches

  • flowers


  • plant habit, early summer

    plant habit, early summer

  • fruit, leaves and thorns.

    fruit, leaves and thorns.