North America Native Plant

Koolau Range Melicope

Botanical name: Melicope lydgatei

USDA symbol: MELY

Life cycle: perennial

Habit: shrub

Native status: Native to Hawaii  

Synonyms: Pelea apoda H. St. John (PEAP)  âš˜  Pelea descendens H. St. John (PEDE9)  âš˜  Pelea lydgatei Hillebr. (PELY)  âš˜  Pelea parvifolia Hillebr. var. apoda (H. St. John) B.C. Stone (PEPAA)  âš˜  Pelea parvifolia Hillebr. var. sessilis (Levl.) B.C. Stone (PEPAS)  âš˜  Pelea semiternata H. St. John (PESE9)   

Koolau Range Melicope: A Rare Hawaiian Treasure Worth Protecting If you’re passionate about native Hawaiian plants and conservation, the Koolau Range melicope (Melicope lydgatei) might just capture your heart. This remarkable shrub represents one of Hawaii’s most precious botanical treasures – and unfortunately, one of its most endangered. What Makes ...

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

Koolau Range Melicope: A Rare Hawaiian Treasure Worth Protecting

If you’re passionate about native Hawaiian plants and conservation, the Koolau Range melicope (Melicope lydgatei) might just capture your heart. This remarkable shrub represents one of Hawaii’s most precious botanical treasures – and unfortunately, one of its most endangered.

What Makes This Plant Special?

The Koolau Range melicope is a perennial shrub that’s perfectly at home in Hawaii’s lush mountain forests. As a multi-stemmed woody plant, it typically grows to heights of 13-16 feet, though it can vary depending on environmental conditions. What makes this plant truly special isn’t just its botanical characteristics – it’s the fact that you’re looking at a living piece of Hawaiian natural heritage.

Where Does It Come From?

This endemic Hawaiian species calls the Koolau Mountains on Oahu home, where it grows naturally in the island’s native forest ecosystems. You won’t find this plant anywhere else in the world – Hawaii is its one and only native range.

The Reality Check: Why This Plant Needs Our Help

Here’s where things get serious. The Koolau Range melicope has a Global Conservation Status of S1, which means it’s critically imperiled. With typically five or fewer occurrences and very few remaining individuals (fewer than 1,000), this species is listed as Endangered in the United States. In other words, this isn’t just rare – it’s teetering on the edge of extinction.

Should You Grow It?

The short answer is: only if you can source it responsibly. If you’re considering adding this plant to your garden, please ensure you’re obtaining it through legitimate conservation programs, botanical gardens, or certified native plant nurseries. Never collect plants from the wild – every individual in nature is precious for the species’ survival.

What Role Can It Play in Your Garden?

If you’re lucky enough to obtain responsibly sourced Koolau Range melicope, it can serve several important purposes:

  • Anchor plant for native Hawaiian gardens
  • Conservation focal point in botanical collections
  • Educational specimen for demonstrating Hawaiian plant conservation
  • Part of habitat restoration projects

Growing Conditions and Care

This species has a wetland status of Facultative, meaning it can handle both wetland and non-wetland conditions. However, successful cultivation requires understanding its natural habitat preferences.

Ideal growing conditions include:

  • USDA Hardiness Zones 10-11 (tropical conditions)
  • Moist, well-draining soils
  • Partial shade mimicking forest understory conditions
  • Consistent moisture without waterlogging
  • Protection from strong winds and direct sun

Planting and Care Tips

Growing critically endangered plants requires extra attention to detail:

  • Plant in well-amended soil with good organic content
  • Provide consistent watering but ensure excellent drainage
  • Mulch around the base to retain moisture and suppress weeds
  • Monitor closely for any signs of stress or disease
  • Consider joining or supporting conservation groups working to protect this species

The Bigger Picture

While the Koolau Range melicope’s specific wildlife and pollinator benefits aren’t well-documented, native Hawaiian plants like this one play crucial roles in supporting endemic insects and maintaining ecosystem balance. By growing this plant responsibly, you’re not just adding an interesting specimen to your garden – you’re participating in conservation efforts that could help save a species from extinction.

The Bottom Line

The Koolau Range melicope represents both an incredible opportunity and a serious responsibility. If you have the chance to grow this rare endemic Hawaiian shrub, approach it with the respect and care it deserves. Always source responsibly, provide excellent care, and consider yourself a guardian of one of Hawaii’s most endangered botanical treasures. After all, gardening with rare natives isn’t just about what grows in your yard – it’s about what survives for future generations.

Koolau 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 lydgatei (Hillebr.) T.G. Hartley & B.C. Stone - Koolau 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