North America Native Plant

Candlewood

Botanical name: Phialanthus myrtilloides

USDA symbol: PHMY

Life cycle: perennial

Habit: shrub

Native status: Native to Puerto Rico  

Candlewood: A Rare Puerto Rican Native Worth Knowing If you’re a plant enthusiast with a passion for rare and unique species, you may have stumbled across Phialanthus myrtilloides, commonly known as candlewood. This intriguing Puerto Rican native is one of those plants that makes you wonder what secrets the tropical ...

Rare plant alert!

Region: Conservation status by state

Status: S2S4: 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) ⚘ Apparently Secure: Uncommon but not rare, and usually widespread. Possibly cause for longterm concern. Typically more than 100 occurrences in the state or more than 10,000 individuals ⚘

Candlewood: A Rare Puerto Rican Native Worth Knowing

If you’re a plant enthusiast with a passion for rare and unique species, you may have stumbled across Phialanthus myrtilloides, commonly known as candlewood. This intriguing Puerto Rican native is one of those plants that makes you wonder what secrets the tropical forests still hold.

What Is Candlewood?

Candlewood is a perennial shrub that’s exclusively native to Puerto Rico. Like many shrubs, it’s a multi-stemmed woody plant that typically stays under 13-16 feet tall, though it can sometimes grow taller or develop a single stem depending on its environment. Think of it as nature’s way of adapting to whatever conditions come its way.

Where Does Candlewood Grow?

This plant calls Puerto Rico home and only Puerto Rico. It’s what botanists call an endemic species, meaning it evolved in this specific location and doesn’t naturally occur anywhere else in the world. That makes it pretty special – and pretty vulnerable.

Rarity Alert: Handle With Care

Here’s something important to know: candlewood has a conservation status of S2S4, which indicates it may be rare or uncommon in its native habitat. This means we need to be extra thoughtful about how we approach growing this plant.

If you’re considering adding candlewood to your garden, please only use plants from responsible sources that don’t harvest from wild populations. Better yet, consider supporting conservation efforts in Puerto Rico that work to protect this and other native species in their natural habitats.

The Mystery Plant Challenge

Here’s where candlewood becomes a bit of a puzzle for gardeners. Despite its intriguing name and native status, there’s surprisingly little information available about its specific growing requirements, appearance, or garden performance. This lack of horticultural information suggests it’s not commonly cultivated, even in its native Puerto Rico.

What We Don’t Know (Yet)

Unfortunately, details about candlewood’s specific needs remain elusive:

  • Preferred soil conditions and pH requirements
  • Water and sunlight preferences
  • Mature size and growth rate
  • Flower characteristics and blooming season
  • Wildlife and pollinator relationships
  • Propagation methods

Should You Grow Candlewood?

Given its rarity status and the limited information available, candlewood might not be the best choice for most home gardeners. Instead, consider supporting its conservation by:

  • Learning more about Puerto Rican native plants and their conservation needs
  • Supporting botanical gardens and conservation organizations working with rare species
  • Choosing other Puerto Rican natives that are more readily available and better understood for cultivation

The Bigger Picture

Candlewood reminds us that there’s still so much we don’t know about the plant kingdom, especially when it comes to rare species in specific locations. While we may not be growing this particular shrub in our backyards anytime soon, it serves as a fascinating example of the unique biodiversity found in places like Puerto Rico.

Sometimes the most important thing we can do for a rare plant is simply to learn about it, appreciate its existence, and support the conservation efforts that help protect it in its natural habitat. In the case of candlewood, that might just be the best gardening advice of all.

Candlewood

Classification

Group

Dicot

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision

Spermatophyta - Seed plants

Division

Magnoliophyta - Flowering plants

Subdivision
Class

Magnoliopsida - Dicotyledons

Subclass

Asteridae

Order

Rubiales

Family

Rubiaceae Juss. - Madder family

Genus

Phialanthus Griseb. - phialanthus

Species

Phialanthus myrtilloides Griseb. - candlewood

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