North America Native Plant

Broad-leaf Yellow Loosestrife

Botanical name: Lysimachia pendens

USDA symbol: LYPE3

Life cycle: perennial

Habit: shrub

Native status: Native to Hawaii  

Broad-leaf Yellow Loosestrife: A Critically Endangered Hawaiian Treasure Meet Lysimachia pendens, commonly known as broad-leaf yellow loosestrife – a plant so rare that most gardeners will never have the chance to encounter it. This Hawaiian endemic holds the sobering distinction of being one of the world’s most endangered flowering plants, ...

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

Broad-leaf Yellow Loosestrife: A Critically Endangered Hawaiian Treasure

Meet Lysimachia pendens, commonly known as broad-leaf yellow loosestrife – a plant so rare that most gardeners will never have the chance to encounter it. This Hawaiian endemic holds the sobering distinction of being one of the world’s most endangered flowering plants, making it more of a conservation conversation piece than a typical garden addition.

A Plant on the Brink

Before we dive into any growing tips, let’s address the elephant in the room: broad-leaf yellow loosestrife is critically imperiled. With a Global Conservation Status of S1 and listed as Endangered in the United States, this perennial shrub teeters on the edge of extinction. We’re talking about a species with typically five or fewer known occurrences and fewer than 1,000 remaining individuals in the wild. That’s rarer than many animals you see in zoo conservation programs!

Where in the World?

This elusive beauty calls Hawaii home – and only Hawaii. As a true Hawaiian endemic, broad-leaf yellow loosestrife represents the unique evolutionary story of the islands, having developed in isolation over thousands of years.

What Does It Look Like?

Lysimachia pendens grows as a perennial, multi-stemmed woody shrub. Like many of its shrubby cousins, it typically stays under 13-16 feet in height, with several stems emerging from near the ground. However, given its rarity, detailed descriptions of its appearance in cultivation are virtually non-existent – most of what we know comes from scientific field studies of wild populations.

The Wetland Connection

Here’s one clue about where this plant likes to live: in Hawaii, broad-leaf yellow loosestrife has a Facultative Wetland status. This means it usually occurs in wetlands but can occasionally be found in drier areas. Think of it as a plant that prefers to keep its feet damp but isn’t completely opposed to drier ground.

Should You Grow It?

Here’s where things get complicated. While we’d love to encourage gardeners to help conserve rare plants, Lysimachia pendens presents unique challenges:

  • Extreme rarity: Seeds or plants are essentially unavailable through normal channels
  • Specialized needs: As a Hawaiian endemic, it likely has very specific growing requirements
  • Conservation concerns: Removing material from wild populations could harm remaining plants
  • Climate limitations: Unless you live in Hawaii or a similar tropical climate, success is unlikely

The Responsible Approach

If you’re passionate about Hawaiian plant conservation and happen to live in Hawaii, your best bet is to:

  • Contact local botanical gardens or native plant societies
  • Support habitat conservation efforts
  • Only acquire plants through legitimate conservation programs
  • Never collect from wild populations

Alternative Hawaiian Beauties

Instead of chasing this ultra-rare species, consider supporting Hawaiian conservation by growing other native Hawaiian plants that are more readily available and better suited to cultivation. Many Hawaiian natives offer stunning beauty while helping preserve the islands’ unique botanical heritage.

The Big Picture

Broad-leaf yellow loosestrife serves as a powerful reminder of what we stand to lose. Every critically endangered plant represents thousands of years of evolution and unique genetic material that, once gone, can never be recovered. While most of us won’t be growing this particular species in our gardens, we can all play a role in plant conservation by choosing native plants, supporting habitat preservation, and spreading awareness about endangered species.

Sometimes the most important plants are the ones we admire from afar while working to ensure they have a future in the wild.

Broad-leaf Yellow Loosestrife

Classification

Group

Dicot

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision

Spermatophyta - Seed plants

Division

Magnoliophyta - Flowering plants

Subdivision
Class

Magnoliopsida - Dicotyledons

Subclass

Dilleniidae

Order

Primulales

Family

Primulaceae Batsch - Primrose family

Genus

Lysimachia L. - yellow loosestrife

Species

Lysimachia pendens Marr - broad-leaf yellow loosestrife

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