North America Non-native Plant

Claoxylon Marianum

Botanical name: Claoxylon marianum

USDA symbol: CLMA25

Life cycle: perennial

Native status: Not native but doesn't reproduce and persist in the wild

Claoxylon marianum: A Hidden Gem of Hawaiian Native Flora If you’re passionate about native Hawaiian plants or working on a restoration project in the islands, you might have come across Claoxylon marianum. This lesser-known native shrub doesn’t get the spotlight like its flashier cousins, but it plays an important role ...

Claoxylon marianum: A Hidden Gem of Hawaiian Native Flora

If you’re passionate about native Hawaiian plants or working on a restoration project in the islands, you might have come across Claoxylon marianum. This lesser-known native shrub doesn’t get the spotlight like its flashier cousins, but it plays an important role in Hawaii’s unique ecosystem.

What is Claoxylon marianum?

Claoxylon marianum is a small to medium-sized native Hawaiian shrub that belongs to the spurge family (Euphorbiaceae). While it may not have a widely recognized common name, this unassuming plant has been quietly contributing to Hawaii’s biodiversity for centuries.

Where Does It Come From?

This plant is endemic to the Hawaiian Islands, meaning it evolved here and exists nowhere else in the world naturally. It’s part of Hawaii’s precious native flora that makes the islands so botanically unique.

Should You Plant Claoxylon marianum?

The answer depends entirely on where you live and what you’re trying to achieve in your garden:

  • Perfect for Hawaiian native gardens: If you’re in Hawaii and want to support native biodiversity, this is an excellent choice
  • Great for restoration projects: Ideal for those working to restore native Hawaiian ecosystems
  • Not suitable for mainland gardens: This tropical native won’t survive in most mainland US climates
  • Supports local wildlife: Provides habitat and food sources for native Hawaiian insects and birds

Growing Claoxylon marianum Successfully

If you’re lucky enough to garden in Hawaii’s tropical climate, here’s what this native shrub needs to thrive:

Climate Requirements

  • USDA hardiness zones 10-12 only
  • Warm, humid tropical conditions year-round
  • No tolerance for frost or freezing temperatures

Ideal Growing Conditions

  • Partial shade to filtered sunlight
  • Well-draining soil that doesn’t stay waterlogged
  • Regular moisture but not constantly wet conditions
  • Protection from strong winds

Planting and Care Tips

  • Plant in spring or early summer for best establishment
  • Water regularly during the first year while roots develop
  • Mulch around the base to retain moisture and suppress weeds
  • Minimal pruning needed – just remove dead or damaged branches
  • Be patient – like many native plants, it may grow slowly at first

Role in Your Landscape

Claoxylon marianum works beautifully as an understory shrub in native Hawaiian landscapes. It’s perfect for creating natural-looking plantings under larger native trees or as part of a mixed native shrub border. While it won’t be the star of your garden with showy flowers, it provides important ecological value and authentic Hawaiian character to your landscape.

Benefits for Wildlife

Although specific pollinator relationships aren’t well-documented, native Hawaiian plants like Claoxylon marianum typically support native insects, which in turn support native birds. By choosing native plants, you’re helping maintain the delicate web of relationships that keep Hawaiian ecosystems healthy.

The Bottom Line

Claoxylon marianum isn’t a plant for every garden, but in the right setting – a Hawaiian native garden – it’s absolutely worth considering. If you’re on the mainland, focus on natives from your own region instead. But for Hawaiian gardeners committed to preserving and celebrating their islands’ unique natural heritage, this quiet native deserves a spot in your landscape planning.

Remember to source your plants from reputable native plant nurseries to ensure you’re getting truly local genetics and supporting responsible propagation practices.

Claoxylon Marianum

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

Euphorbiales

Family

Euphorbiaceae Juss. - Spurge family

Genus

Claoxylon A. Juss. - claoxylon

Species

Claoxylon marianum Müll. Arg.

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