Family: Solanaceae

Origin, Description & Uses
Marmalade bush (Streptosolen jamesonii) is a colorful flowering shrub native to the Andean regions of Ecuador and Peru. It is prized for its clusters of bright orange to yellow, trumpet-shaped flowers that bloom over a long season and attract butterflies, bees, and other pollinators. Growing to about 4–6 feet (1–2 m) tall, this evergreen shrub is commonly used as an ornamental hedge, accent plant, or container specimen in tropical and subtropical gardens. Its vibrant flowers and relatively easy maintenance have made it a popular landscaping plant throughout warm climates, including Hawaiʻi.

Risks & Threats
Although Streptosolen jamesonii is considered a low-risk species, it has become naturalized on Kauaʻi and is potentially naturalizing on Maui and Hawaiʻi Island. The species may spread beyond cultivation through seed production or vegetative growth, particularly in favorable moist environments. However, there is currently little evidence that it forms dense infestations, significantly alters native ecosystems, or displaces native vegetation. Continued observation is recommended in areas where it is spreading, but based on available information, marmalade bush is not considered a major invasive threat in Hawaiʻi and remains a suitable choice for ornamental planting when managed responsibly.

High Risk Traits:

• High climate suitability for tropical/subtropical zones
  
• Native to and naturalized in tropical regions
  
• Widely introduced as ornamental outside native range
  
• Naturalized in Hawaii (Kauai)
  
• Host for Potato spindle tuber viroid and pests (aphids, whiteflies, spider mites)
  
• Tolerates sandy loam to clay loam soils
  
• Produces viable seed
  
• Propagules dispersed intentionally by people (ornamental trade)
  
• Minute seeds in dry capsules adapted for wind dispersal
  
• Tolerates and benefits from heavy pruning

Low Risk Traits:

• Narrow climate versatility (USDA zones 9b–11 only)
  
• Not an agricultural, forestry, or horticultural weed
  
• No weedy congeners (monotypic genus)
  
• Lacks spines, thorns, or burrs
  
• Low allergenicity
  
• No fire hazard (rainforest habitat)
  
• Not shade tolerant (requires full sun)
  
• No vegetative reproduction
  
• Not dispersed as produce contaminant
  
• Not water dispersed
  
• Not bird dispersed (dry capsules, not fleshy)
  
• No external animal dispersal (no hooks or sticky attachments)
  
• No gut passage survival (not consumed by animals)