North America Native Plant

Puerto Rico Ironweed

Botanical name: Vernonia borinquensis

USDA symbol: VEBO2

Life cycle: perennial

Habit: vine

Native status: Native to Puerto Rico  

Synonyms: Lepidaploa borinquensis (Urb.) H. Rob. (LEBO10)   

Puerto Rico Ironweed: A Critically Rare Caribbean Native Worth Protecting Meet Puerto Rico ironweed (Vernonia borinquensis), one of the Caribbean’s most endangered native shrubs. This perennial beauty might not be sitting pretty in your local nursery, but it deserves a spot in our conservation conversation. If you’re lucky enough to ...

Rare plant alert!

Region: Conservation status by state

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) ⚘

Puerto Rico Ironweed: A Critically Rare Caribbean Native Worth Protecting

Meet Puerto Rico ironweed (Vernonia borinquensis), one of the Caribbean’s most endangered native shrubs. This perennial beauty might not be sitting pretty in your local nursery, but it deserves a spot in our conservation conversation. If you’re lucky enough to encounter this rare gem, you’re looking at a true botanical treasure that’s hanging on by a thread in its native Puerto Rico.

What Makes Puerto Rico Ironweed Special?

Puerto Rico ironweed is a multi-stemmed woody shrub that typically grows less than 13-16 feet tall. As a member of the aster family, it likely produces the characteristic small, clustered flowers that ironweeds are known for, though specific details about its blooms remain elusive due to its rarity.

Also known scientifically as Lepidaploa borinquensis, this perennial shrub has adapted to life in Puerto Rico’s unique island ecosystem. Its facultative wetland status means it’s flexible about moisture levels, equally at home in wet and dry conditions – a handy trait for surviving in varied Caribbean microclimates.

Where Does It Call Home?

This endemic species is found exclusively in Puerto Rico, making it a true island original. Unfortunately, Puerto Rico ironweed has become critically imperiled, with only five or fewer known populations and fewer than 1,000 individual plants remaining in the wild.

A Conservation Challenge Worth Taking On

Here’s where things get serious, fellow gardeners. Puerto Rico ironweed carries a Global Conservation Status of S1, meaning it’s critically imperiled and extremely vulnerable to extinction. This isn’t just another pretty plant – it’s a living piece of Puerto Rico’s natural heritage that desperately needs our help.

Should you plant it? Yes, but only if you can source it responsibly from conservation organizations or authorized native plant societies. Never collect this plant from the wild – doing so could literally push it closer to extinction.

Growing Puerto Rico Ironweed: What We Know

Unfortunately, detailed cultivation information for this rare species is limited, which isn’t surprising given its critically endangered status. Here’s what we can piece together:

  • Growth habit: Multi-stemmed perennial shrub
  • Height: Typically under 13-16 feet
  • Moisture tolerance: Adaptable to both wet and dry conditions
  • Climate: Tropical Caribbean conditions

The Role It Could Play in Your Garden

If you’re gardening in Puerto Rico or a similar tropical climate, Puerto Rico ironweed could serve as a mid-height shrub in native plant gardens focused on conservation. Its adaptability to different moisture levels makes it potentially valuable for transition areas between wet and dry garden zones.

However, given its rarity, this plant is better suited for:

  • Conservation gardens
  • Native plant preservation projects
  • Educational botanical displays
  • Research and propagation efforts

Supporting Conservation Efforts

While you might not be able to grow Puerto Rico ironweed in your backyard tomorrow, you can still make a difference. Support local botanical gardens, native plant societies, and conservation organizations working to preserve Puerto Rico’s unique flora. Sometimes the best way to garden is to protect the wild spaces where rare plants like this one struggle to survive.

If you do encounter responsibly propagated Puerto Rico ironweed, treat it like the botanical royalty it is. Give it the respect of a plant that represents thousands of years of evolution on a unique island ecosystem – because that’s exactly what it is.

Remember, every rare plant we lose makes our world a little less diverse, a little less resilient, and a little less wonderful. Puerto Rico ironweed might be small in numbers, but it’s mighty in importance.

Puerto Rico Ironweed

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

Asterales

Family

Asteraceae Bercht. & J. Presl - Aster family

Genus

Vernonia Schreb. - ironweed

Species

Vernonia borinquensis Urb. - Puerto Rico ironweed

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