Family: Acanthaceae

Origin, Description & Uses
Odontonema tubaeforme (fire spike) is native to southern Mexico through Colombia, where it grows in warm, humid tropical environments. It is an evergreen shrub known for its upright growth habit and striking spikes of bright red, tubular flowers that often bloom for long periods. Because of its vivid floral display, it is widely planted as an ornamental in tropical and subtropical gardens. It is commonly used in hedges, borders, and pollinator plantings, where it can attract hummingbirds, butterflies, and other nectar-feeding wildlife.

Risks & Threats
Fire spike has traits commonly associated with invasive plant species in island ecosystems, including vigorous growth, tolerance of a range of conditions, and the ability to spread beyond intended planting areas. In suitable climates, it can escape cultivation and form dense stands that compete with and displace native vegetation, potentially reducing habitat quality for native species. Although this species is currently not known to be naturalized in the Hawaiian Islands, it does possess traits that are cause for concern, and which could detrimentally impact tropical island ecosystems. When available, choosing a low-risk or native alternative is recommended to help protect Hawaii’s unique natural environments.

High Risk Traits:

• Naturalized in Florida, Australia, French Polynesia, Hawaii, Samoa, Lord Howe Island
  
• Environmental weed, forms dense monospecific stands in wet forests
  
• Thrives in tropical/subtropical climates
  
• Broad climate suitability (elevation range 0–1400 m)
  
• Shade tolerant
  
• Tolerates wide range of soil types
  
• Forms dense thickets
  
• Reproduces by vegetative fragmentation
  
• Propagules dispersed unintentionally (garden waste dumping) and intentionally (ornamental)
  
• Water-dispersed propagules
  
• Tolerates mutilation/cutting (rejuvenates after severe pruning)

Low Risk Traits:

• No spines, thorns, or burrs
  
• Not allelopathic, parasitic, or toxic
  
• Not a fire hazard
  
• Requires specialist pollinators (limits seed set in some regions)
  
• Seed production infrequent in cultivation
  
• Not wind-dispersed, bird-dispersed, or externally animal-dispersed