Family: Passifloraceae

Origin, Description & Uses
Passiflora quadrangularis (giant granadilla) is a vigorous tropical vine native to northern South America, from Colombia to Brazil. It is best known for its very large, fragrant flowers and exceptionally large edible fruits, which are used fresh or in juices and desserts. The plant has been widely introduced to tropical regions around the world, including Hawaiʻi prior to 1871, where it is grown in cultivation and can be found in wet and mesic forest areas. In Hawaiʻi, it is naturalized on Oʻahu and Hawaiʻi Island, with populations on Kauaʻi considered potentially naturalizing.

Risks & Threats
Giant granadilla is a fast-growing climbing vine that can smother and overtop native vegetation, forming dense growth that reduces light availability and alters forest structure. In Hawaiʻi, it is naturalized and possesses traits that are cause for concern, including vigorous growth, effective seed dispersal, and tolerance of a range of wet tropical conditions. These characteristics increase its potential to spread into natural areas and negatively impact tropical island ecosystems, especially in lowland and wet forest habitats. Because of these risks, choosing low-risk or native alternatives is strongly recommended when suitable options are available.

High Risk Traits:

• Broad climate tolerance (0–2500 m; zones 10a-11)
  
• Naturalized in tropics (Hawaii, Galapagos)
  
• Naturalized on O'ahu & Hawai'i; potentially naturalizing on Kaua'i
  
• Repeated introductions & naturalized beyond native range
  
• Weed (garden, environmental, congeneric)
  
• Toxic to humans (cyanide in leaves; toxic pulp/root)
  
• Wide soil tolerance
  
• Climbing/smothering liana
  
• Self-compatible; viable seed
  
• Vegetative reproduction (congeners)
  
• Flowers in 1-2 years
  
• Dispersed intentionally (cultivation), by birds, & via gut passage

Low Risk Traits:

• No spines/thorns/burrs
  
• No allelopathy, parasitism, animal toxicity, pests/pathogens, or fire hazard
  
• Not shade tolerant (needs sun)
  
• No unintentional, wind, water, external, or contaminant dispersal
  
• Low seed production (16–50 fruits/vine)