Family: Fabaceae

Origin, Description & Uses:
Sigmoidotropis speciosa is a twining perennial vine native to tropical Asia. It produces vigorous climbing stems with trifoliate leaves and attractive purple to violet pea-like flowers followed by slender seed pods. The species has been cultivated as an ornamental because of its showy blooms and lush foliage and has also been used locally as a cover plant and for erosion control in some tropical regions due to its rapid growth and ability to cover fences, trellises, and disturbed ground.

Risks & Threats:
Sigmoidotropis speciosa is naturalized in Hawaiʻi, with established populations on Kauaʻi and Oʻahu and reports of potential naturalization on Maui. It possesses traits that are cause for concern, including vigorous growth, prolific seed production, and the ability to spread into disturbed habitats where it may climb over and smother surrounding vegetation. Although it is not currently considered among Hawaiʻi’s highest-risk invasive plants, ongoing evaluation is needed to determine its long-term impacts on native ecosystems and managed landscapes. Caution is recommended when planting this species, and monitoring should be undertaken to ensure it does not spread beyond cultivation or negatively impact Hawaiʻi’s unique tropical island ecosystems. Whenever possible, consider choosing a low-risk or native alternative.

High Risk Traits:

• Broad climate tolerance (15–1500 m elevation)
  
• Naturalized in Florida & Hawaii (Oʻahu, Kauaʻi, Maui)
  
• Congeners are agricultural/environmental weeds
  
• Vigorous climbing/smothering vine (up to 6 m)
  
• Nitrogen-fixing (alters soil nutrients)
  
• Produces viable seed & reseeds freely
  
• Dispersed intentionally (ornamental/lei flower)
  
• Potential produce contaminant (potted plants)

Low Risk Traits:

• No spines, thorns, or burrs
  
• Non-toxic to humans/animals (palatable)
  
• No wind, bird, or external animal dispersal