Family: Bignoniaceae

Origin, Description & Uses: Crescentia cujete, commonly known as the calabash tree, is native to tropical regions of Central America, the Caribbean, and northern South America. It is a small to medium-sized tree with a spreading form, smooth gray bark, and distinctive round, hard-shelled fruits that grow directly from the trunk and branches. The tree produces greenish-yellow, tubular flowers that are often pollinated by bats. Traditionally, the dried fruits have been widely used to make bowls, cups, musical instruments, and other household items, while different parts of the tree have also been used in traditional medicine. Today, the calabash tree is commonly planted as an ornamental or cultural plant in tropical landscapes.

Risks, Threats & Management: The calabash tree is considered low risk and is not known to be invasive in Hawaiʻi. It generally reproduces slowly and does not readily spread beyond cultivated settings. At this time, there are no significant ecological threats associated with its use in landscaping. As with all non-native plants, it is best managed by planting thoughtfully, monitoring for unexpected spread, and avoiding disposal of plant material in natural areas to help protect Hawaiʻi’s unique ecosystems.

High Risk Traits:

• Highly suited to tropical/subtropical climates
  
• Repeatedly introduced outside native range
  
• Seeds survive gut passage (dispersed by animals)
  
• Tolerates wide soil range
  
• Intentionally propagated by people

Low Risk Traits:

• Not reported as weedy or invasive
  
• No vegetative reproduction
  
• Large fruits with low seed output
  
• Not toxic to animals or humans
  
• Not allelopathic, parasitic, or thorny
  
• Requires full sun (shade intolerant)
  
• No fire risk
  
• Slow maturation (4+ years to reproduce)
  
• Requires specialist pollinators (bats)