Family: Pandanaceae

Origin, Description & Uses
Pandanus pygmaeus is a compact, dwarf screwpine native to the dry and coastal regions of northern and eastern Madagascar. It forms low, clumping rosettes of stiff, narrow leaves with characteristic spiny margins arranged in a spiral pattern. Compared to larger pandanus species, it remains small and shrub-like, making it especially useful in landscaping where space is limited. Its bold, architectural form makes it popular in tropical and subtropical gardens, including rock gardens, container plantings, and drought-tolerant (xeriscape) designs.

Risks & Threats
This species is generally considered low risk in cultivation, with no known tendency to become invasive outside its native range and no significant toxicity concerns reported for landscape use. The primary threats are environmental rather than ecological: in Madagascar, habitat loss and degradation of dry and coastal ecosystems may impact wild populations. In cultivation, it is limited mainly by sensitivity to cold temperatures and poor tolerance of waterlogged soils, which can restrict where it can be successfully grown.

High Risk Traits:

• Produces spines/thorny leaves and fruit
  
• Native to tropical/subtropical climates (Madagascar, Malesia)
  
• High climate suitability and good climate match
  
• Produces viable seed (sold commercially)
  
• Reproduces vegetatively (branches root on soil contact)
  
• Intentionally dispersed by people (ornamental, sold online)
  
• Water-dispersed propagules (coastal habitat, likely sea-drifted)

Low Risk Traits:

• No evidence of naturalization or weedy races
  
• No repeated introductions outside native range
  
• Not allelopathic, parasitic, or toxic to animals
  
• No fire hazard, dense thickets, or climbing habit
  
• Dioecious (requires both sexes for seed set)
  
• No evidence of prolific seed production or persistent seed bank
  
• No unintentional, wind, bird, external animal, or gut-passage dispersal