North America Native Plant

Gibson’s Cyanea

Botanical name: Cyanea macrostegia gibsonii

USDA symbol: CYMAG

Life cycle: perennial

Habit: tree

Native status: Native to Hawaii  

Synonyms: Cyanea gibsonii Hillebr. (CYGI4)   

Gibson’s Cyanea: A Rare Hawaiian Native Worth Protecting Meet Gibson’s cyanea (Cyanea macrostegia gibsonii), one of Hawaii’s most striking—and most endangered—native trees. This remarkable member of the bellflower family stands as a living testament to the unique beauty of Hawaiian flora, though sadly, it’s becoming increasingly rare in the wild. ...

Rare plant alert!

Region: United States

Status: S3T1: Status is uncertain but is somewhere between the following rankings: Subspecies or variety is critically Imperiled: Extremely rare due to factor(s) making it especially vulnerable to extinction. Typically 5 or fewer occurrences or very few remaining individuals (<1,000) ⚘ Vulnerable: Either very rare and local throughout its range, found only in a restricted range (even if abundant at some locations), or factors are making it vulnerable to extinction. Typically 21 to 100 occurrences or between 3,000 and 10,000 individuals ⚘ Endangered: In danger of extinction throughout all or a significant portion of its range. ⚘

Region: United States

Gibson’s Cyanea: A Rare Hawaiian Native Worth Protecting

Meet Gibson’s cyanea (Cyanea macrostegia gibsonii), one of Hawaii’s most striking—and most endangered—native trees. This remarkable member of the bellflower family stands as a living testament to the unique beauty of Hawaiian flora, though sadly, it’s becoming increasingly rare in the wild.

What Makes Gibson’s Cyanea Special?

Gibson’s cyanea is a true showstopper in the plant world. This perennial tree typically grows 13-16 feet tall (sometimes taller under ideal conditions), featuring a single, sturdy trunk topped with a dramatic crown of large, palmate leaves. Think of it as nature’s own tropical umbrella, but way more elegant.

Also known by its botanical synonym Cyanea gibsonii, this species belongs to that wonderful group of plants that makes Hawaii’s forests so uniquely magical. Its impressive stature and distinctive foliage make it a natural focal point in any landscape lucky enough to host it.

Where Does It Call Home?

Gibson’s cyanea is endemic to Hawaii, meaning you won’t find it growing wild anywhere else on Earth. This tree has evolved specifically for the Hawaiian islands’ unique climate and ecosystem, thriving in the moist, tropical forests that characterize much of the archipelago.

A Plant in Peril: Understanding Its Endangered Status

Here’s where things get serious: Gibson’s cyanea is listed as Endangered in the United States, with a Global Conservation Status of S3T1. This means every single plant matters tremendously for the species’ survival. Habitat loss, invasive species, and other environmental pressures have pushed this beautiful tree to the brink.

If you’re considering growing Gibson’s cyanea, please only source plants from reputable native plant nurseries or conservation programs. Never collect from the wild—every wild plant is crucial for the species’ survival.

Growing Gibson’s Cyanea: For the Dedicated Tropical Gardener

Let’s be honest: this isn’t a plant for everyone. Gibson’s cyanea requires very specific conditions that limit its cultivation to USDA hardiness zones 10-12. If you live in a tropical or subtropical climate and want to help conserve this species, here’s what you need to know:

Ideal Growing Conditions

  • Light: Partial shade to filtered sunlight (mimics its natural forest habitat)
  • Soil: Rich, organic, well-draining soil that stays consistently moist
  • Humidity: High humidity levels (think tropical rainforest vibes)
  • Protection: Shelter from strong winds, which can damage its large leaves

Care Tips for Success

  • Water regularly but ensure good drainage—soggy roots spell trouble
  • Mulch around the base to retain moisture and suppress weeds
  • Provide organic matter regularly to mimic forest floor conditions
  • Be patient—this is a slow-growing species that rewards long-term thinking

Why Grow Gibson’s Cyanea?

Beyond its obvious aesthetic appeal as a striking specimen tree, growing Gibson’s cyanea serves a greater purpose. This species plays an important role in supporting native Hawaiian wildlife, particularly native birds that have co-evolved with Hawaii’s unique flora.

In a garden setting, it works beautifully as:

  • A dramatic focal point in tropical landscapes
  • Part of native Hawaiian plant collections
  • An educational specimen highlighting conservation needs
  • A living piece of Hawaiian natural heritage

The Bottom Line

Gibson’s cyanea isn’t just another pretty plant—it’s a conservation story with roots (literally) in one of the world’s most unique ecosystems. If you have the right climate and growing conditions, and can source plants responsibly, growing this endangered beauty is both a gardening adventure and a conservation act.

Remember, every cultivated Gibson’s cyanea represents hope for the species’ future. While most of us can only admire this remarkable tree from afar, those in tropical zones have the opportunity to be part of its conservation story. Just make sure you’re getting your plants from ethical sources—because in the world of endangered species, every single plant counts.

Gibson’s Cyanea

Classification

Group

Dicot

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision

Spermatophyta - Seed plants

Division

Magnoliophyta - Flowering plants

Subdivision
Class

Magnoliopsida - Dicotyledons

Subclass

Asteridae

Order

Campanulales

Family

Campanulaceae Juss. - Bellflower family

Genus

Cyanea Gaudich. - cyanea

Species

Cyanea macrostegia Hillebr. - purple cyanea

Plant data source: USDA, NRCS 2025. The PLANTS Database. https://plants.usda.gov,. 2/25/2025. National Plant Data Team, Greensboro, NC USA