North America Native Plant

Haupa Mountain Melicope

Botanical name: Melicope haupuensis

USDA symbol: MEHA3

Life cycle: perennial

Habit: tree

Native status: Native to Hawaii  

Synonyms: Pelea haupuensis H. St. John (PEHA7)   

Haupa Mountain Melicope: A Rare Hawaiian Treasure Worth Protecting Meet the Haupa Mountain melicope (Melicope haupuensis), one of Hawaii’s most endangered native trees. This remarkable species represents both the incredible biodiversity of the Hawaiian Islands and the urgent need for plant conservation. While you might not find this tree at ...

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

Haupa Mountain Melicope: A Rare Hawaiian Treasure Worth Protecting

Meet the Haupa Mountain melicope (Melicope haupuensis), one of Hawaii’s most endangered native trees. This remarkable species represents both the incredible biodiversity of the Hawaiian Islands and the urgent need for plant conservation. While you might not find this tree at your local nursery, understanding its story helps us appreciate the delicate balance of native ecosystems.

What Makes This Plant Special?

The Haupa Mountain melicope is a perennial tree that typically grows over 13-16 feet tall, though environmental conditions can sometimes result in shorter, multi-stemmed forms. As a member of the citrus family, it shares characteristics with other Melicope species but has evolved unique traits specific to its Hawaiian home.

This tree was previously known by the scientific synonym Pelea haupuensis, named by botanist Harold St. John, but has since been reclassified under the genus Melicope.

Where Does It Grow?

This endemic species is found exclusively in Hawaii, making it a true island treasure. The Haupa Mountain melicope has adapted to Hawaii’s unique climate and growing conditions over thousands of years.

A Critical Conservation Alert

Important: The Haupa Mountain melicope is critically imperiled with a Global Conservation Status of S1 and is listed as Endangered in the United States. This means there are typically only 5 or fewer occurrences in the wild, with very few remaining individuals (fewer than 1,000 plants total).

If you’re interested in growing this species, it’s crucial to source plants only from legitimate conservation programs or botanical institutions. Never collect seeds or cuttings from wild populations, as this could further threaten the species’ survival.

Growing Conditions and Care

For those fortunate enough to obtain responsibly sourced Haupa Mountain melicope plants, here’s what you need to know:

  • Climate: Thrives in USDA hardiness zones 10-11, requiring tropical to subtropical conditions
  • Soil: Prefers well-draining soils that mimic Hawaiian volcanic conditions
  • Light: Adapts to partial shade or full sun conditions
  • Water: Requires consistent moisture and humidity
  • Protection: Benefits from wind protection, especially when young

Role in Native Hawaiian Gardens

In appropriate settings, the Haupa Mountain melicope serves as:

  • A conservation showcase specimen
  • An educational tool about Hawaiian plant diversity
  • A centerpiece for native Hawaiian landscape designs
  • Part of habitat restoration efforts

This tree is best suited for specialized native Hawaiian gardens, botanical collections, or conservation-focused landscapes rather than typical residential gardens.

Supporting Conservation Efforts

While most gardeners won’t have the opportunity to grow Haupa Mountain melicope directly, you can still make a difference:

  • Support Hawaiian native plant conservation organizations
  • Choose other native Hawaiian plants for your garden
  • Learn about and share information about endangered species
  • Visit botanical gardens that maintain conservation collections

The Bigger Picture

The story of Melicope haupuensis reminds us that every native plant species plays a vital role in its ecosystem. While we may not know all the specific wildlife benefits this tree provides, its rarity suggests it once filled an important ecological niche in Hawaiian forests.

By understanding and respecting rare species like the Haupa Mountain melicope, we become better stewards of all native plants. Whether you’re growing common natives in your backyard or supporting conservation efforts from afar, every action counts in preserving our botanical heritage for future generations.

Remember: if you ever encounter information about acquiring this rare species, always verify that sources are legitimate and conservation-focused. The survival of the Haupa Mountain melicope depends on responsible stewardship by everyone who cares about Hawaii’s unique natural heritage.

Haupa Mountain 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 haupuensis (H. St. John) T.G. Hartley & B.C. Stone - Haupa Mountain melicope

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