North America Native Plant

Pua’ainaka

Botanical name: Stenogyne rotundifolia

USDA symbol: STRO2

Life cycle: perennial

Habit: vine

Native status: Native to Hawaii  

Synonyms: Stenogyne affinis Forbes var. degeneri Sherff (STAFD)  âš˜  Stenogyne glabrata (Hillebr.) Sherff (STGL2)  âš˜  Stenogyne rotundifolia A. Gray var. oblonga Sherff (STROO)  âš˜  Stenogyne sessilis Benth. var. hexanthoides O. Deg. & Sherff (STSEH2)   

Pua’ainaka: A Rare Hawaiian Native Worth Protecting in Your Garden Meet pua’ainaka (Stenogyne rotundifolia), a charming but increasingly rare Hawaiian native that deserves a special place in conservation-minded gardens. This humble perennial herb might not win any beauty contests with its small white flowers, but what it lacks in showiness, ...

Rare plant alert!

Region: Conservation status by state

Status: S3: 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 ⚘

Pua’ainaka: A Rare Hawaiian Native Worth Protecting in Your Garden

Meet pua’ainaka (Stenogyne rotundifolia), a charming but increasingly rare Hawaiian native that deserves a special place in conservation-minded gardens. This humble perennial herb might not win any beauty contests with its small white flowers, but what it lacks in showiness, it more than makes up for in ecological importance and cultural significance.

What Makes Pua’ainaka Special?

Pua’ainaka is a low-growing forb—essentially a soft-stemmed plant without woody tissue—that belongs exclusively to the Hawaiian Islands. Unlike flashy introduced ornamentals, this native species has been quietly supporting Hawaiian ecosystems for thousands of years, developing alongside native pollinators and wildlife.

The plant gets its scientific name from its distinctive rounded leaves (rotundifolia means round-leaved), which form attractive ground-hugging rosettes. While the flowers are small and white, they’re perfectly designed for Hawaii’s native insects and small pollinators.

Where Does Pua’ainaka Come From?

This endemic species calls multiple Hawaiian islands home, naturally occurring on Kauai, Oahu, Molokai, Maui, and the Big Island. You won’t find pua’ainaka growing wild anywhere else in the world—it’s a true Hawaiian original.

A Conservation Concern: Why Rarity Matters

Here’s where things get serious: pua’ainaka has a Global Conservation Status of S3, meaning it’s considered vulnerable to extinction. With typically only 21 to 100 occurrences remaining and between 3,000 and 10,000 individual plants in the wild, this species needs our help to survive.

If you’re considering adding pua’ainaka to your garden, please only source plants from reputable native plant nurseries that propagate from ethically collected seeds or cuttings. Never collect plants from the wild—every individual in nature is precious for the species’ survival.

Growing Pua’ainaka: What You Need to Know

The good news? Once you source plants responsibly, pua’ainaka is relatively easy to grow in the right conditions. Here’s what this Hawaiian native prefers:

  • Climate: USDA zones 10-11 (tropical and subtropical areas)
  • Light: Partial shade to full sun
  • Soil: Well-draining soils with moderate moisture
  • Water: Regular watering during establishment, then drought-tolerant
  • Maintenance: Minimal care required once established

Perfect for Native Hawaiian Gardens

Pua’ainaka shines in several garden scenarios:

  • Native Hawaiian gardens: Essential for authentic indigenous plant communities
  • Restoration projects: Helps rebuild damaged native ecosystems
  • Naturalistic landscapes: Provides subtle groundcover that looks right at home
  • Erosion control: Those low-growing habits help stabilize slopes naturally

Wildlife and Ecological Benefits

While pua’ainaka might seem modest, it plays important ecological roles. The flowers attract native Hawaiian insects and small pollinators, supporting the intricate web of relationships that make Hawaiian ecosystems function. As a facultative wetland plant, it can grow in both wetland and non-wetland areas, making it adaptable to various moisture conditions.

Should You Grow Pua’ainaka?

If you live in Hawaii or another suitable tropical climate, absolutely—but with important caveats. Growing pua’ainaka helps preserve genetic diversity and provides insurance populations against extinction. However, this should only be done responsibly:

  • Source plants only from reputable native plant nurseries
  • Never collect from wild populations
  • Consider participating in organized conservation efforts
  • Share seeds or cuttings with other conservation-minded gardeners

The Bottom Line

Pua’ainaka may not be the most glamorous plant in your garden, but growing it makes you part of an important conservation story. By providing this vulnerable species with safe garden habitat, you’re helping ensure that future generations can experience this authentic piece of Hawaiian natural heritage. In a world where we’re losing native plants at an alarming rate, every garden that welcomes species like pua’ainaka becomes a small sanctuary—and that’s pretty special indeed.

Pua’ainaka

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

Lamiales

Family

Lamiaceae Martinov - Mint family

Genus

Stenogyne Benth. - stenogyne

Species

Stenogyne rotundifolia A. Gray - pua'ainaka

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