Family: Proteaceae

Protea cynaroides, commonly known as king protea, is native to South Africa and is the country’s national flower. It is best known for its spectacular, dinner-plate–sized flower heads surrounded by colorful, petal-like bracts that range from soft pink to deep red. The plant is a woody shrub rather than a true tree, with thick stems and leathery evergreen leaves adapted to dry, nutrient-poor soils. King protea is widely cultivated as an ornamental for landscapes and gardens and is especially prized in the cut-flower industry for its long-lasting, dramatic blooms.

In Hawaiʻi, Protea cynaroides is generally considered low risk and is not known to aggressively spread or invade natural areas. It grows slowly, has specific soil and climate requirements, and typically relies on cultivation rather than natural regeneration. While it can persist where planted, there is little evidence that king protea displaces native species or alters ecosystems. As with any non-native plant, responsible planting and monitoring are encouraged, but at this time the species poses minimal threat to Hawaiʻi’s environment.

High Risk Traits:

• Grows in maritime, Mediterranean climates
  
• Reported to be naturalized and/or a weed but evidence is inconclusive
  
• From fire-prone ecosystem. May increase fire risk in introduced range
  
• Tolerates many soil types
  
• Reproduces by seeds
  
• May hybridize with other Protea species
  
• Seeds dispersed by wind and intentionally by people
  
• Birds and rodents may secondarily disperse seeds (but may primarily be seed predators)
  
• Serotinous seeds form a persistent canopy “seed bank”
  
• Tolerates regular pruning

Low Risk Traits:

• Unarmed (no spines, thorns, or burrs)
  
• Non-toxic
  
• Ornamental
  
• Requires full sun
  
• Self-incompatible
  
• Reaches maturity in 4-5 years
  
• Not reported to spread vegetatively
  
• Relatively large, serotinous seeds unlikely to be inadvertently dispersed