Family: Asteraceae

Brazilian button flower (Centratherum punctatum), also known as larkdaisy or porcupine flower, is a small flowering plant in the sunflower family (Asteraceae) native to tropical regions of South America. It is commonly grown as an ornamental for its round, purple flower heads and soft, dark green leaves, which may have a light pineapple scent when crushed. This plant is typically grown as a short-lived perennial or annual and is often used in garden beds, borders, and landscapes in warm climates because it is easy to grow and tolerates sunny, dry conditions with little maintenance.

Despite its ornamental appeal, Brazilian button flower has shown a strong ability to escape cultivation and become established in the wild. It is already naturalized on multiple Hawaiian Islands, where it spreads readily by wind-dispersed seeds and is frequently found along roadsides, pastures, and other disturbed areas. While it does not usually form dense infestations or heavily invade intact native forests, its ability to spread easily and persist without care makes it a concern in managed landscapes. Because of this, planting alternatives that are non-invasive or native is encouraged to help reduce further spread and protect Hawaiʻi’s natural ecosystems.

High Risk Traits:

• Naturalized outside its native range, including across multiple Hawaiian Islands
  
• Well suited to tropical and subtropical climates, with broad climate tolerance
  
• Broad environmental tolerance, including elevation range from lowlands to montane areas
  
• Escapes cultivation and persists as a garden, roadside, and disturbance weed
  
• Produces viable seed and self-sows readily
  
• Short generation time (often annual or short-lived perennial)
  
• Seeds adapted for wind dispersal (pappus-bearing achenes)
  
• Likely dispersed unintentionally along roads, trails, and disturbed sites
  
• Intentionally spread by people as an ornamental plant
  
• Established seed dispersal pathways via horticulture and landscaping
  
• Widely distributed across disturbed habitats, including pastures, roadsides, and urban cracks

Low Risk Traits:

• No evidence of strong environmental impacts in intact natural ecosystems
  
• Not known to be allelopathic
  
• Not aquatic and does not invade wetlands
  
• No spines, thorns, or burrs
  
• No documented human toxicity or allergenic effects
  
• No evidence of significant fire risk
  
• Not shade-tolerant, favoring open, sunny conditions
  
• No confirmed persistent soil seed bank