Native Plants

Ulihi Phyllostegia

Phyllostegia glabra

USDA symbol: PHGL7

perennial forb

Hawaii: native

If you’re passionate about native Hawaiian plants and want to make a meaningful contribution to conservation, ulihi phyllostegia (Phyllostegia glabra) might just be the perfect addition to your garden. This charming little perennial herb is more than just a pretty face – it’s a rare treasure that needs our help ...

Ulihi Phyllostegia may be listed as rare in your area.
Global Conservation Status

Status: S3 | Vulnerable: Found only in a restricted range (even if abundant at some locations). Typically 21 to 100 occurrences or between 3,000 and 10,000 individuals.

Ulihi Phyllostegia: A Rare Hawaiian Native Worth Protecting in Your Garden

If you’re passionate about native Hawaiian plants and want to make a meaningful contribution to conservation, ulihi phyllostegia (Phyllostegia glabra) might just be the perfect addition to your garden. This charming little perennial herb is more than just a pretty face – it’s a rare treasure that needs our help to survive.

What Makes Ulihi Phyllostegia Special?

Ulihi phyllostegia is a delicate herbaceous perennial that’s endemic to the Hawaiian Islands. As a forb – basically a non-woody flowering plant – it stays low to the ground and produces lovely small tubular flowers that range from white to pale purple. The flowers are arranged in terminal spikes above small, serrated oval leaves, creating a subtle but charming display that fits perfectly into naturalistic Hawaiian gardens.

This native Hawaiian plant grows naturally on several islands including Oahu, Molokai, and Maui, where it thrives in the understory of native forests.

  • Species observed
  • No observations

Why This Plant Needs Your Help

Important Conservation Note: Ulihi phyllostegia has a Global Conservation Status of S3, which means it’s considered vulnerable. With only 21 to 100 known occurrences and an estimated 3,000 to 10,000 individuals remaining, this species is at risk of disappearing from the wild. If you choose to grow this plant, please make sure you source it responsibly from reputable native plant nurseries or conservation programs – never collect from wild populations.

Where Ulihi Phyllostegia Fits in Your Garden

This native Hawaiian gem works beautifully as:

  • Ground cover in shaded native plant gardens
  • Understory plantings beneath larger native trees and shrubs
  • Part of habitat restoration projects
  • Addition to naturalistic landscape designs focused on Hawaiian flora

Its small stature and preference for partial to full shade make it an excellent choice for filling in the lower levels of a native Hawaiian garden ecosystem.

Growing Conditions and Care

Ulihi phyllostegia is suited for USDA hardiness zones 10-12, making it perfect for tropical and subtropical climates. Here’s what this little beauty needs to thrive:

Light: Partial to full shade – think forest understory conditions
Soil: Well-draining soil that doesn’t get waterlogged
Water: Consistent moderate moisture (it’s classified as facultative upland, meaning it usually prefers non-wetland conditions but can handle some moisture)
Protection: Shelter from strong winds

Planting and Care Tips

  • Plant in areas that mimic its natural forest understory habitat
  • Provide organic mulch to help retain moisture and suppress weeds
  • Water regularly but ensure good drainage to prevent root rot
  • Protect from harsh direct sunlight, especially during the hottest parts of the day
  • Be patient – as with many native plants, establishment may take some time

Benefits to Local Wildlife

While ulihi phyllostegia may be small, it plays an important role in supporting native Hawaiian pollinators. Its tubular flowers are perfectly sized for native Hawaiian bees and other small pollinators, making it a valuable addition to any wildlife-friendly garden.

Should You Plant Ulihi Phyllostegia?

If you’re committed to native Hawaiian gardening and can source this plant responsibly, absolutely! By growing ulihi phyllostegia in your garden, you’re not just adding a unique native plant – you’re participating in conservation efforts to protect a vulnerable species. Just remember that with rarity comes responsibility: always purchase from reputable sources and consider participating in or supporting conservation programs that work to protect this special plant.

For gardeners outside of Hawaii or those in unsuitable climates, consider supporting Hawaiian plant conservation organizations or choosing native plants appropriate for your own region instead.

Classification

Group: Dicot
Kingdom: Plantae - Plants
Subkingdom: Tracheobionta - Vascular plants
Superdivision: Spermatophyta - Seed plants
Division: Magnoliophyta - Flowering plants
Class: Magnoliopsida - Dicotyledons
Subclass: Asteridae
Order: Lamiales
Family: Lamiaceae Martinov - Mint family
Genus: Phyllostegia Benth. - phyllostegia

Species: Phyllostegia glabra (Gaudich.) Benth. - ulihi phyllostegia

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