North America Native Plant

Treetrunk Cyanea

Botanical name: Cyanea copelandii copelandii

USDA symbol: CYCOC

Life cycle: perennial

Habit: vine

Native status: Native to Hawaii  

Treetrunk Cyanea: A Rare Hawaiian Native Worth Protecting Meet the treetrunk cyanea (Cyanea copelandii copelandii), a remarkable native Hawaiian shrub that’s as unique as its name suggests. This perennial beauty belongs to the bellflower family and represents one of Hawaii’s precious endemic treasures – though sadly, it’s one that’s increasingly ...

Rare plant alert!

Region: United States

Status: S1TH: Status is uncertain but is somewhere between the following rankings: 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) ⚘ Endangered: In danger of extinction throughout all or a significant portion of its range. ⚘

Region: United States

Treetrunk Cyanea: A Rare Hawaiian Native Worth Protecting

Meet the treetrunk cyanea (Cyanea copelandii copelandii), a remarkable native Hawaiian shrub that’s as unique as its name suggests. This perennial beauty belongs to the bellflower family and represents one of Hawaii’s precious endemic treasures – though sadly, it’s one that’s increasingly rare in the wild.

A True Hawaiian Native

The treetrunk cyanea is exclusively native to Hawaii, making it a genuine piece of the islands’ natural heritage. This shrub grows naturally only in Hawaiian ecosystems, where it has evolved alongside other native species for thousands of years. Its presence in a garden connects you directly to Hawaii’s unique botanical legacy.

What Makes This Plant Special

As a multi-stemmed woody shrub, the treetrunk cyanea typically reaches heights of 13-16 feet, though it can grow taller or remain single-stemmed depending on environmental conditions. Its growth habit creates an interesting architectural element in the landscape, with several stems arising from or near the ground level.

Being a perennial, this plant will grace your garden year after year, developing character and presence as it matures. The treetrunk portion of its common name hints at its substantial, woody nature that sets it apart from more delicate flowering plants.

Important Conservation Alert

Before considering this plant for your garden, here’s what you absolutely need to know: The treetrunk cyanea is listed as Endangered in the United States. This means it’s facing a very real risk of extinction in the wild. While this makes it incredibly special, it also means we must be extremely careful about how we approach growing it.

If you’re interested in cultivating this rare beauty, please only source material from reputable native plant nurseries or conservation programs that can guarantee the plants were propagated responsibly – never collected from wild populations.

Growing Conditions and Care

The treetrunk cyanea thrives in tropical conditions, making it suitable for USDA hardiness zones 10-12. This means it’s primarily suited for:

  • Hawaiian gardens and landscapes
  • Southern Florida locations
  • Protected tropical microclimates in other warm regions
  • Greenhouse cultivation in cooler climates

As a native Hawaiian species, it’s perfectly suited for native plant gardens, conservation landscapes, and restoration projects. Its shrub form makes it excellent for creating natural screens, adding vertical interest, or serving as a focal point in native plant collections.

Why Consider This Plant?

Despite its rarity challenges, there are compelling reasons to consider the treetrunk cyanea:

  • Conservation impact: Growing this species helps preserve Hawaiian biodiversity
  • Authentic native landscaping: Perfect for true Hawaiian native plant gardens
  • Educational value: A living example of Hawaii’s unique flora
  • Long-term beauty: Perennial growth means lasting garden value

The Bottom Line

The treetrunk cyanea represents both an opportunity and a responsibility. While it can be a stunning addition to appropriate tropical gardens, its endangered status means it’s not a casual gardening choice. If you’re passionate about Hawaiian native plants and committed to conservation, this species could be a meaningful addition to your landscape – but only when sourced through proper channels.

For most gardeners interested in Hawaiian natives, consider starting with more common native species while supporting conservation efforts for rarities like the treetrunk cyanea. Every responsibly grown native plant, whether common or rare, contributes to preserving Hawaii’s incredible botanical heritage for future generations.

Treetrunk 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 copelandii Rock - treetrunk cyanea

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