North America Native Plant

Waihanau Lobelia

Botanical name: Lobelia dunbarii dunbarii

USDA symbol: LODUD3

Life cycle: perennial

Habit: shrub

Native status: Native to Hawaii  

Waihanau Lobelia: A Rare Hawaiian Native Worth Knowing About If you’re passionate about Hawaiian native plants, you may have come across the intriguing Waihanau lobelia (Lobelia dunbarii dunbarii). This lesser-known member of the bellflower family represents one of Hawaii’s unique endemic treasures, though information about this particular subspecies remains surprisingly ...

Waihanau Lobelia: A Rare Hawaiian Native Worth Knowing About

If you’re passionate about Hawaiian native plants, you may have come across the intriguing Waihanau lobelia (Lobelia dunbarii dunbarii). This lesser-known member of the bellflower family represents one of Hawaii’s unique endemic treasures, though information about this particular subspecies remains surprisingly scarce in gardening circles.

What Makes Waihanau Lobelia Special

The Waihanau lobelia is a perennial shrub that’s exclusively native to Hawaii. As a true Hawaiian endemic, this plant evolved in isolation over thousands of years, making it a living piece of the islands’ natural heritage. The plant typically grows as a multi-stemmed woody shrub, usually reaching heights of less than 13 to 16 feet, though it can occasionally grow taller or develop a single stem depending on environmental conditions.

Where You’ll Find It Growing Wild

This native beauty calls the Hawaiian Islands home, where it has adapted to the unique microclimates and conditions found nowhere else on Earth. Its distribution appears to be limited to Hawaii, making it a truly special plant for those interested in authentic island flora.

Should You Plant Waihanau Lobelia in Your Garden?

Here’s where things get a bit tricky for the home gardener. While supporting native Hawaiian plants is always admirable, the Waihanau lobelia presents some challenges:

  • Limited availability: This plant is extremely rare in cultivation
  • Unknown growing requirements: Specific care instructions are not well documented
  • Potential conservation concerns: The scarcity of information suggests this may be a rare subspecies

The Responsible Approach

If you’re determined to grow this native Hawaiian beauty, here’s what you need to know:

Source responsibly: Only obtain plants from reputable native plant nurseries that can guarantee the plants were ethically propagated, not collected from wild populations.

Consider alternatives: While researching the perfect native plant for your Hawaiian garden, you might want to explore other Lobelia species or Hawaiian natives that are better understood and more readily available.

Contribute to conservation: If you do manage to grow this plant successfully, consider sharing your experience with local botanical gardens or native plant societies. Your knowledge could help preserve this species for future generations.

Growing Conditions (Best Guess)

Since specific growing information for Waihanau lobelia is limited, we can make educated guesses based on other Hawaiian lobelias:

  • Likely prefers partial shade to filtered sunlight
  • Probably needs well-draining soil with good organic content
  • May require consistent moisture without waterlogging
  • Best suited for USDA zones 10-12 (or similar tropical conditions)

The Bottom Line

The Waihanau lobelia is undoubtedly a fascinating native plant that deserves recognition and protection. However, for most home gardeners, this shrub remains more of a botanical curiosity than a practical garden choice. If you’re passionate about Hawaiian natives, consider starting with better-documented species while keeping an eye out for more information about this elusive beauty.

Sometimes the most valuable thing we can do for a rare native plant is simply to learn about it, appreciate it, and support the researchers and conservationists working to understand and protect it. The Waihanau lobelia may be waiting for its moment in the gardening spotlight – and that moment might come when we know more about how to grow it successfully.

Waihanau Lobelia

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

Lobelia L. - lobelia

Species

Lobelia dunbarii Rock - Waihanau lobelia

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