North America Native Plant

Waianae Range Melicope

Botanical name: Melicope christophersenii

USDA symbol: MECH2

Life cycle: perennial

Habit: shrub

Native status: Native to Hawaii  

Synonyms: Pelea christophersenii H. St. John (PECH2)  âš˜  Pelea kauaensis H. St. John (PEKA4)  âš˜  Pelea storeyana H. St. John & Hume (PEST5)   

Waianae Range Melicope: A Critically Endangered Hawaiian Native Worth Protecting If you’re passionate about native Hawaiian plants and conservation gardening, you’ve probably never heard of the Waianae Range melicope (Melicope christophersenii). And honestly, that’s not surprising—this remarkable little shrub is one of Hawaii’s rarest native plants, teetering on the edge ...

Rare plant alert!

Region: United States

Status: S1: Status is uncertain but is somewhere between the following rankings: Critically Imperiled: Extremely rare due to factor(s) making it especially vulnerable to extinction. Typically 5 or fewer occurrences or very few remaining individuals (<1,000) ⚘ Endangered: In danger of extinction throughout all or a significant portion of its range. ⚘

Region: United States

Waianae Range Melicope: A Critically Endangered Hawaiian Native Worth Protecting

If you’re passionate about native Hawaiian plants and conservation gardening, you’ve probably never heard of the Waianae Range melicope (Melicope christophersenii). And honestly, that’s not surprising—this remarkable little shrub is one of Hawaii’s rarest native plants, teetering on the edge of extinction in the wild.

What Makes This Plant So Special?

The Waianae Range melicope is a perennial shrub that’s completely endemic to Hawaii, meaning it exists nowhere else on Earth. This multi-stemmed woody plant typically grows to less than 13-16 feet tall, making it perfect for smaller native gardens. Like other members of the Melicope genus, it produces clusters of small, white to cream-colored flowers that add a delicate beauty to any landscape.

You might also see this plant listed under its former scientific names, including Pelea christophersenii, Pelea kauaensis, and Pelea storeyana—botanists have been busy reclassifying this group over the years!

Where Does It Come From?

Here’s where things get both fascinating and heartbreaking: the Waianae Range melicope is found only in the Waianae Mountains on the island of Oahu. Its incredibly limited native range makes it one of Hawaii’s most geographically restricted plants.

The Reality Check: This Plant Is in Serious Trouble

Before you start planning where to plant your Waianae Range melicope, there’s something crucial you need to know. This species has a Global Conservation Status of S1, which means it’s critically imperiled. We’re talking about typically 5 or fewer occurrences in the wild, with fewer than 1,000 individuals remaining. In the United States, it’s officially listed as Endangered.

What does this mean for you as a gardener? If you’re lucky enough to find this plant available, you should absolutely consider growing it—but only if you can source it responsibly. Never collect plants from the wild, and only purchase from reputable native plant nurseries that propagate their stock ethically.

Growing Conditions and Care

The Waianae Range melicope is suited for USDA hardiness zones 10-12, which makes sense given its tropical Hawaiian origins. Based on its natural habitat in the Waianae Mountains, this shrub likely prefers:

  • Well-draining soils
  • Partial shade to full sun exposure
  • Protection from strong winds
  • Moderate watering (it has a Facultative Upland wetland status, meaning it usually grows in non-wetland areas)

Perfect for Conservation Gardens

This isn’t your typical landscape shrub—it’s a plant with a mission. The Waianae Range melicope is perfect for:

  • Native Hawaiian plant gardens
  • Conservation-focused landscapes
  • Educational gardens that showcase rare species
  • Specialized collections of endemic Hawaiian plants

While we don’t have detailed information about its specific wildlife benefits, native Hawaiian plants like this one typically support native insects and birds that have evolved alongside them over thousands of years.

The Bottom Line

Should you plant a Waianae Range melicope? Absolutely—if you can source it responsibly and you’re committed to being part of its conservation story. Every plant grown in cultivation is potentially a genetic lifeline for this critically endangered species.

Just remember: with great rarity comes great responsibility. If you’re fortunate enough to grow this plant, consider yourself a conservation gardener participating in one of Hawaii’s most important botanical rescue missions. And who knows? Your garden might just help save a species from extinction.

That’s pretty amazing for a little shrub most people have never heard of, don’t you think?

Waianae Range Melicope

Classification

Group

Dicot

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision

Spermatophyta - Seed plants

Division

Magnoliophyta - Flowering plants

Subdivision
Class

Magnoliopsida - Dicotyledons

Subclass

Rosidae

Order

Sapindales

Family

Rutaceae Juss. - Rue family

Genus

Melicope (J.R. Forst. & G. Forst.) T.G. Hartley & B.C. Stone - melicope

Species

Melicope christophersenii (H. St. John) T.G. Hartley & B.C. Stone - Waianae Range melicope

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