North America Native Plant

Oahu Clermontia

Botanical name: Clermontia oblongifolia oblongifolia

USDA symbol: CLOBO

Life cycle: perennial

Habit: shrub

Native status: Native to Hawaii  

Synonyms: Clermontia aspera E. Wimm. p.p. (CLAS)   

Oahu Clermontia: A Rare Hawaiian Native Worth Preserving in Your Garden Meet the Oahu clermontia (Clermontia oblongifolia oblongifolia), a stunning Hawaiian native that deserves a special place in tropical gardens. This remarkable shrub isn’t just another pretty face in the plant world – it’s a living piece of Hawaii’s natural ...

Rare plant alert!

Region: Conservation status by state

Status: S3T3: Status is uncertain but is somewhere between the following rankings: 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 ⚘ Subspecies or variety is 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. ⚘

Oahu Clermontia: A Rare Hawaiian Native Worth Preserving in Your Garden

Meet the Oahu clermontia (Clermontia oblongifolia oblongifolia), a stunning Hawaiian native that deserves a special place in tropical gardens. This remarkable shrub isn’t just another pretty face in the plant world – it’s a living piece of Hawaii’s natural heritage that’s become increasingly rare in the wild.

What Makes Oahu Clermontia Special?

As a true Hawaiian endemic, the Oahu clermontia is found nowhere else on Earth except the island of Oahu. This perennial shrub typically grows as a multi-stemmed woody plant, usually staying under 13-16 feet tall, making it a perfect size for residential landscapes. Its beautiful purple tubular flowers and attractive foliage make it a real showstopper when it blooms.

Geographic Distribution and Native Status

This special plant calls only Hawaii home, specifically the island of Oahu. It’s what botanists call an endemic species – meaning it evolved in this one location and exists naturally nowhere else in the world.

A Plant That Needs Our Help

Here’s something important to know: the Oahu clermontia has a conservation status of S3T3, which indicates it’s facing some level of concern in the wild. This makes it all the more valuable to cultivate responsibly in our gardens. If you’re considering adding this beauty to your landscape, make sure you source it from reputable nurseries that propagate plants ethically rather than collecting from wild populations.

Why Grow Oahu Clermontia?

There are several compelling reasons to include this native Hawaiian shrub in your garden:

  • Conservation impact: By growing native plants, you’re helping preserve Hawaii’s unique botanical heritage
  • Wildlife support: Native Hawaiian plants like this one support the islands’ specialized wildlife, including native birds
  • Authentic landscaping: Perfect for creating genuine Hawaiian native plant gardens
  • Unique beauty: Its distinctive purple flowers and growth form add tropical elegance to any landscape

Growing Conditions and Care

The Oahu clermontia thrives in Hawaii’s tropical climate, which falls within USDA hardiness zones 10-11. If you’re lucky enough to live in these zones, here’s what this plant prefers:

  • Light: Partial shade to filtered sunlight works best
  • Soil: Well-draining, moist soil that doesn’t become waterlogged
  • Water: Regular watering to maintain consistent moisture
  • Protection: Shield from strong winds that can damage the branches

Perfect for Native Hawaiian Landscapes

This shrub shines brightest in native Hawaiian garden designs where it can be paired with other indigenous plants. It works beautifully as a specimen plant where its unique form and flowers can be appreciated up close. In larger landscapes, it can be grouped with other native Hawaiian shrubs to create authentic island ecosystems.

Planting and Care Tips

When planting your Oahu clermontia, choose a location with morning sun and afternoon shade. Dig a hole twice as wide as the root ball but no deeper, and backfill with well-amended soil. Water regularly, especially during dry periods, but ensure the soil drains well to prevent root rot.

Regular light pruning can help maintain its shape, and a layer of organic mulch around the base will help retain moisture and suppress weeds.

Supporting Conservation Through Gardening

By choosing to grow the Oahu clermontia, you’re not just adding beauty to your landscape – you’re participating in conservation. Every responsibly grown native plant in our gardens helps ensure these species survive for future generations. Just remember to source your plants from reputable nurseries that propagate rather than wild-collect, and consider sharing seeds or cuttings with other conservation-minded gardeners.

The Oahu clermontia proves that the best gardens are those that celebrate and protect the unique natural heritage of their place. In Hawaii, that means giving native plants like this rare beauty the spotlight they deserve.

Oahu Clermontia

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

Clermontia Gaudich. - clermontia

Species

Clermontia oblongifolia Gaudich. - Oahu clermontia

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