North America Native Plant

Kauai Clubmoss

Botanical name: Huperzia subintegra

USDA symbol: HUSU4

Life cycle: perennial

Habit: subshrub

Native status: Native to Hawaii  

Synonyms: Lycopodium serratum Thunb. var. subintegrum Hillebr. (LYSES)   

Kauai Clubmoss: A Living Fossil for Your Hawaiian Garden Meet one of nature’s most ancient survivors: the Kauai clubmoss (Huperzia subintegra). This fascinating little plant isn’t actually a moss at all, but rather a lycopod – think of it as a living fossil that’s been hanging around since dinosaurs roamed ...

Kauai Clubmoss: A Living Fossil for Your Hawaiian Garden

Meet one of nature’s most ancient survivors: the Kauai clubmoss (Huperzia subintegra). This fascinating little plant isn’t actually a moss at all, but rather a lycopod – think of it as a living fossil that’s been hanging around since dinosaurs roamed the Earth. If you’re gardening in Hawaii and want to add something truly unique to your landscape, this endemic Hawaiian beauty might just be the prehistoric touch your garden needs.

What Exactly Is Kauai Clubmoss?

Don’t let the name fool you – Kauai clubmoss is actually a type of primitive vascular plant called a lycopod or clubmoss. These ancient plants reproduce using spores instead of seeds or flowers, making them living relics from a time when giant ferns dominated the landscape. The Kauai clubmoss forms small, dense mats with tiny, scale-like leaves that create an almost moss-like appearance, hence the common name.

As a perennial forb herb, this plant lacks significant woody tissue and maintains its structure close to or at ground level. What makes it particularly special is its club-shaped reproductive structures (sporangia) that give clubmosses their distinctive name.

Where Does It Call Home?

Kauai clubmoss is a true Hawaiian endemic, meaning it naturally occurs nowhere else on Earth except the Hawaiian Islands. You’ll find this special plant growing in Hawaii’s unique ecosystems, where it has evolved to thrive in the islands’ specific climate conditions.

Is It Beneficial for Your Garden?

Absolutely! Here’s why Kauai clubmoss can be a wonderful addition to the right garden setting:

  • Native authenticity: As an endemic Hawaiian species, it provides genuine ecological value and supports local biodiversity
  • Unique texture: Its moss-like appearance creates interesting textural contrast in shade gardens
  • Low maintenance: Once established in suitable conditions, it requires minimal care
  • Educational value: It’s a living piece of natural history that can spark conversations about plant evolution
  • Ground cover potential: Forms attractive, low-growing mats in appropriate settings

How to Identify Kauai Clubmoss

Spotting Kauai clubmoss in the wild or confirming you have the right plant involves looking for these key characteristics:

  • Size and growth pattern: Forms low, creeping mats close to the ground
  • Leaves: Tiny, scale-like leaves arranged spirally around the stems
  • Reproductive structures: Look for small, club-shaped sporangia (spore-bearing structures)
  • Habitat: Typically found in moist, shaded areas with high humidity
  • Texture: Dense, moss-like appearance but with more defined stem structure than true mosses

Perfect Growing Conditions

Kauai clubmoss has some specific preferences that reflect its Hawaiian heritage:

  • Light: Filtered sunlight to partial shade – think forest floor conditions
  • Moisture: Consistent moisture is crucial, but not waterlogged conditions
  • Humidity: High humidity levels (typical of Hawaiian climates)
  • Temperature: Warm, tropical conditions (USDA zones 10-11)
  • Soil: Well-draining but moisture-retentive soil with good organic content

Garden Applications

This unique plant works beautifully in several garden settings:

  • Native Hawaiian gardens: Essential for authentic indigenous plantings
  • Shade gardens: Adds texture and interest to understory plantings
  • Naturalistic landscapes: Perfect for creating wild, forest-like settings
  • Educational gardens: Excellent for demonstrating plant evolution and Hawaiian endemism

Important Considerations

Before you rush out to find Kauai clubmoss for your garden, keep these important points in mind:

As an endemic Hawaiian species, Kauai clubmoss should only be grown if you can provide appropriate tropical conditions. It’s not suitable for mainland gardens or areas outside of tropical/subtropical climates. Additionally, if you’re interested in growing this plant, make sure to source it responsibly from reputable native plant nurseries that propagate rather than wild-collect their specimens.

The plant has facultative wetland status in Hawaii, meaning it can grow in both wetland and non-wetland conditions, giving you some flexibility in placement within appropriate climatic zones.

The Bottom Line

Kauai clubmoss is a remarkable plant that offers Hawaiian gardeners the chance to grow a true living fossil. While it may not provide the showy flowers or dramatic foliage of more common garden plants, it brings something far more valuable: a direct connection to the ancient plant world and Hawaii’s unique natural heritage. If you’re gardening in tropical Hawaii and want to create an authentic native landscape, this prehistoric charmer deserves serious consideration.

Just remember – this isn’t a plant for everyone or everywhere. But in the right Hawaiian garden setting, with proper moisture and shade, Kauai clubmoss can be a fascinating and meaningful addition that connects your landscape to millions of years of natural history.

Wetland Status

The rule of seasoned gardeners and landscapers is to choose the "right plant for the right place" matching plants to their ideal growing conditions, so they'll thrive with less work and fewer inputs. But the simplicity of this catchphrase conceals how tricky plant selection is. While tags list watering requirements, there's more to the story.

Knowing a plant's wetland status can simplify the process by revealing the interaction between plants, water, and soil. Surprisingly, many popular landscape plants are wetland species! And what may be a wetland plant in one area, in another it might thrive in drier conditions. Also, it helps you make smarter gardening choices and grow healthy plants with less care and feeding, saving you time, frustration, and money while producing an attractive garden with greater ecological benefits.

Regions
Status
Moisture Conditions

Hawaii

FAC

Facultative - Plants with this status can occur in wetlands and non-wetlands

Kauai Clubmoss

Classification

Group

Lycopod

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision
Division

Lycopodiophyta - Lycopods

Subdivision
Class

Lycopodiopsida

Subclass
Order

Lycopodiales

Family

Lycopodiaceae P. Beauv. ex Mirb. - Club-moss family

Genus

Huperzia Bernh. - clubmoss

Species

Huperzia subintegra (Hillebr.) Beitel & W.H. Wagner - Kauai clubmoss

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