North America Native Plant

Stahl’s Stopper

Botanical name: Eugenia stahlii

USDA symbol: EUST3

Life cycle: perennial

Habit: tree

Native status: Native to Puerto Rico  

Stahl’s Stopper: A Rare Puerto Rican Treasure Worth Protecting If you’re passionate about native plants and conservation, Stahl’s stopper might just capture your heart. This remarkable tree, scientifically known as Eugenia stahlii, represents one of Puerto Rico’s botanical gems—though like many treasures, it’s become increasingly rare and precious. What Makes ...

Rare plant alert!

Region: Conservation status by state

Status: S2: 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) ⚘

Stahl’s Stopper: A Rare Puerto Rican Treasure Worth Protecting

If you’re passionate about native plants and conservation, Stahl’s stopper might just capture your heart. This remarkable tree, scientifically known as Eugenia stahlii, represents one of Puerto Rico’s botanical gems—though like many treasures, it’s become increasingly rare and precious.

What Makes Stahl’s Stopper Special?

Stahl’s stopper is a perennial evergreen tree that can reach heights of 13 to 16 feet or more under ideal conditions. While it typically grows as a single-trunked tree, environmental factors can sometimes encourage a more compact, multi-stemmed growth form. Its glossy, dark green leaves provide year-round beauty, while delicate white flowers emerge periodically, followed by small dark berries that add seasonal interest.

Where Does It Call Home?

This tree is a true Puerto Rican native, found nowhere else in the world. Eugenia stahlii grows naturally in Puerto Rico’s coastal and limestone forests, where it has adapted to the island’s unique tropical conditions.

A Conservation Success Story in Your Garden

Here’s where things get serious: Stahl’s stopper carries a Global Conservation Status of S2, meaning it’s considered imperiled due to extreme rarity. With typically only 6 to 20 occurrences remaining and an estimated 1,000 to 3,000 individual plants in the wild, this species is especially vulnerable to extinction.

What does this mean for gardeners? If you’re fortunate enough to live in Puerto Rico or a similar tropical climate (USDA zones 10-11), growing Stahl’s stopper can be an incredible way to support conservation efforts. However, it’s absolutely critical that you source plants responsibly from reputable native plant nurseries or conservation programs—never collect from wild populations.

Growing Stahl’s Stopper Successfully

The good news is that Stahl’s stopper can be a rewarding addition to the right garden. Here’s what you need to know:

Ideal Growing Conditions

  • Climate: Tropical and subtropical only (USDA zones 10-11)
  • Sunlight: Partial shade to full sun
  • Soil: Well-draining soils preferred
  • Water: Moderate moisture needs; drought tolerant once established
  • Wetland compatibility: Facultative—can grow in both wetland and non-wetland conditions

Planting and Care Tips

  • Plant in spring or early summer when temperatures are consistently warm
  • Ensure completely frost-free conditions year-round
  • Water regularly during establishment, then reduce frequency as the tree matures
  • Minimal pruning required—this tree naturally maintains an attractive form
  • Mulch around the base to retain moisture and suppress weeds

Garden Design and Landscape Uses

Stahl’s stopper works beautifully as a specimen tree in native Puerto Rican gardens or tropical landscapes. Its moderate size makes it suitable for smaller spaces, while its evergreen nature provides year-round structure. Consider using it as:

  • A focal point in conservation-themed gardens
  • Part of native plant restoration projects
  • A privacy screen or natural barrier
  • An educational specimen to showcase Puerto Rican flora

Supporting Pollinators and Wildlife

The small white flowers of Stahl’s stopper attract native bees and other small pollinators, making it a valuable addition to pollinator-friendly gardens. The resulting berries also provide food sources for local wildlife, helping support Puerto Rico’s native ecosystem.

The Bottom Line: Conservation Through Cultivation

Stahl’s stopper represents both an opportunity and a responsibility. For gardeners in appropriate climates, growing this rare native species can contribute to conservation efforts while adding unique beauty to landscapes. However, the key word here is responsibility—always source plants ethically and never disturb wild populations.

If you’re not in Puerto Rico or a similar tropical zone, consider supporting conservation efforts for Stahl’s stopper through donations to botanical gardens or conservation organizations working to protect Puerto Rican flora. Every small action helps ensure that future generations can appreciate this remarkable tree.

Remember: when we grow rare natives responsibly, we become part of the solution. Stahl’s stopper isn’t just a tree—it’s a living piece of Puerto Rico’s natural heritage that deserves our protection and respect.

Stahl’s Stopper

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

Myrtales

Family

Myrtaceae Juss. - Myrtle family

Genus

Eugenia L. - stopper

Species

Eugenia stahlii (Kiaersk.) Krug & Urb. - Stahl's stopper

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