North America Native Plant

Ridgetop Schiedea

Botanical name: Schiedea mannii

USDA symbol: SCMA4

Life cycle: perennial

Habit: shrub

Native status: Native to Hawaii  

Ridgetop Schiedea: A Rare Hawaiian Native Worth Protecting in Your Garden If you’re passionate about Hawaiian native plants and conservation, you might want to learn about ridgetop schiedea (Schiedea mannii), a remarkable but critically rare shrub that calls Hawaii’s volcanic slopes home. This little-known native deserves attention not just for ...

Rare plant alert!

Region: Conservation status by state

Status: S2: Status is uncertain but is somewhere between the following rankings: Imperiled: Extremely rare due to factor(s) making it especially vulnerable to extinction. Typically 6 to 20 occurrences or few remaining individuals (1,000 to 3,000) ⚘

Ridgetop Schiedea: A Rare Hawaiian Native Worth Protecting in Your Garden

If you’re passionate about Hawaiian native plants and conservation, you might want to learn about ridgetop schiedea (Schiedea mannii), a remarkable but critically rare shrub that calls Hawaii’s volcanic slopes home. This little-known native deserves attention not just for its understated beauty, but for its precarious conservation status that makes every garden specimen count.

What Makes Ridgetop Schiedea Special?

Ridgetop schiedea is a perennial shrub that’s endemic to Hawaii, meaning it exists nowhere else on Earth. This multi-stemmed woody plant typically grows to less than 13-16 feet in height, though it usually stays much smaller in garden settings. Its narrow, linear leaves and delicate clusters of small white to pink flowers give it a subtle, refined appearance that fits perfectly into native Hawaiian landscapes.

Where Does It Grow Naturally?

This rare native is found exclusively in Hawaii, specifically on the islands of Maui and Molokai. In the wild, ridgetop schiedea thrives in dry to mesic (moderately moist) forests at elevations between 1,000 and 4,000 feet, where it has adapted to volcanic soils and the unique climate conditions of Hawaii’s middle elevations.

A Plant in Crisis: Understanding Its Rarity

Here’s where things get serious: ridgetop schiedea has a Global Conservation Status of S2, which classifies it as Imperiled. This means the species is extremely rare and vulnerable to extinction, with typically only 6 to 20 known occurrences and fewer than 1,000 to 3,000 individual plants remaining in the wild. This conservation status should give any gardener pause and inspire a sense of responsibility.

Should You Grow Ridgetop Schiedea?

The short answer is: only if you can source it responsibly. Given its imperiled status, growing ridgetop schiedea can actually be part of conservation efforts, but only when done correctly. Here’s what you need to consider:

  • Only obtain plants from reputable native plant nurseries or botanical institutions
  • Never collect plants from the wild – this could harm remaining populations
  • Consider participating in official conservation programs
  • Ensure you can provide appropriate growing conditions

Growing Conditions and Care

If you decide to grow ridgetop schiedea, you’ll need to recreate its native Hawaiian environment. This plant is suited for USDA hardiness zones 10-11, making it appropriate only for tropical and subtropical climates or greenhouse cultivation in cooler areas.

Ideal Growing Conditions:

  • Well-draining volcanic or sandy soil
  • Partial shade to full sun exposure
  • Protection from strong winds
  • Minimal watering once established (drought-tolerant)
  • Elevations or microclimates that mimic its native habitat

Garden Design and Landscape Role

Ridgetop schiedea works best in specialized native Hawaiian gardens, restoration projects, or botanical collections focused on rare species. Its compact shrub form and subtle flowers make it an excellent choice for:

  • Native plant demonstration gardens
  • Educational landscapes
  • Conservation-focused residential gardens
  • Dry garden or xerophytic plantings

Wildlife and Pollinator Benefits

While specific information about ridgetop schiedea’s wildlife benefits is limited, native Hawaiian plants typically support endemic insects and other native species that have co-evolved with them. By growing this rare native, you’re potentially providing habitat and food sources for Hawaii’s unique native ecosystem.

The Bottom Line

Ridgetop schiedea represents both an opportunity and a responsibility. For gardeners committed to Hawaiian native plant conservation, growing this rare species can be rewarding and meaningful. However, it’s crucial to approach this plant with respect for its conservation status and ensure that any cultivation efforts support, rather than harm, wild populations.

If you’re new to native Hawaiian gardening or can’t source ridgetop schiedea responsibly, consider starting with more common native Hawaiian plants to build your skills and support the native plant community. Every native plant in a garden is a step toward conservation, and ridgetop schiedea will be there when you’re ready to take on the challenge of growing one of Hawaii’s rarest treasures.

Ridgetop Schiedea

Classification

Group

Dicot

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision

Spermatophyta - Seed plants

Division

Magnoliophyta - Flowering plants

Subdivision
Class

Magnoliopsida - Dicotyledons

Subclass

Caryophyllidae

Order

Caryophyllales

Family

Caryophyllaceae Juss. - Pink family

Genus

Schiedea Cham. & Schltdl. - schiedea

Species

Schiedea mannii H. St. John - ridgetop schiedea

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