North America Native Plant

Kauai Bur Cucumber

Botanical name: Sicyos lanceoloideus

USDA symbol: SILA24

Life cycle: annual

Habit: vine

Native status: Native to Hawaii  

Synonyms: Sicyos kaalaensis H. St. John (SIKA3)  âš˜  Sicyos kauaiensis H. St. John (SIKA4)   

Kauai Bur Cucumber: A Critically Endangered Hawaiian Treasure If you’re dreaming of adding the Kauai bur cucumber (Sicyos lanceoloideus) to your garden, you might want to hit the pause button. This isn’t your typical gardening dilemma of will it survive my black thumb? – this is about one of Hawaii’s ...

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

Kauai Bur Cucumber: A Critically Endangered Hawaiian Treasure

If you’re dreaming of adding the Kauai bur cucumber (Sicyos lanceoloideus) to your garden, you might want to hit the pause button. This isn’t your typical gardening dilemma of will it survive my black thumb? – this is about one of Hawaii’s most critically endangered plants that desperately needs our protection rather than our cultivation attempts.

What Makes This Plant Special

The Kauai bur cucumber is a Hawaiian endemic species, meaning it exists nowhere else on Earth except in its native Hawaiian islands. As an annual forb herb in the cucumber family (Cucurbitaceae), this plant completes its entire life cycle within a single growing season. Like other members of its family, it lacks significant woody tissue and dies back completely each year, relying on seeds to continue the next generation.

You might also see this plant referenced by its scientific synonyms Sicyos kaalaensis or Sicyos kauaiensis in older botanical literature, but Sicyos lanceoloideus is the currently accepted name.

Where It Calls Home

This rare beauty is found exclusively in Hawaii, making it a true island endemic. Its distribution is extremely limited, which is part of what makes it so vulnerable to extinction.

The Harsh Reality: Why You Shouldn’t Grow It

Here’s where we need to have a serious conversation. The Kauai bur cucumber has a Global Conservation Status of S1, which translates to Critically Imperiled. In plain English, this means:

  • There are typically 5 or fewer known occurrences in the wild
  • Fewer than 1,000 individual plants likely exist
  • The species is at extreme risk of extinction
  • It’s officially listed as Endangered

This isn’t a plant you can responsibly add to your weekend garden center shopping list. In fact, attempting to collect seeds or plants from the wild would be both illegal and potentially devastating to the remaining population.

What We Don’t Know (And Why That Matters)

One of the most telling aspects of this species is how little we know about its basic growing requirements. Details about its preferred growing conditions, pollinator relationships, wildlife benefits, and even its exact appearance are poorly documented. This knowledge gap exists precisely because the plant is so rare that there have been limited opportunities to study it thoroughly.

If You’re Passionate About Hawaiian Plants

If you’re drawn to Hawaiian native plants (and who could blame you?), consider these alternatives that you can actually grow responsibly:

  • Support Hawaiian plant conservation organizations financially
  • Volunteer with habitat restoration projects
  • Choose other Hawaiian native plants that aren’t endangered for your garden
  • Spread awareness about the importance of protecting rare species

The Bottom Line

Sometimes the most loving thing we can do for a plant is to admire it from afar and ensure its wild populations have the best chance of survival. The Kauai bur cucumber needs conservation efforts, habitat protection, and scientific study – not well-meaning gardeners accidentally contributing to its decline.

If you’re interested in supporting conservation efforts for this and other endangered Hawaiian plants, reach out to local botanical gardens, native plant societies, or conservation organizations. They can direct you toward species that actually benefit from cultivation and ways you can help protect treasures like the Kauai bur cucumber for future generations.

Kauai Bur Cucumber

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

Violales

Family

Cucurbitaceae Juss. - Cucumber family

Genus

Sicyos L. - bur cucumber

Species

Sicyos lanceoloideus (H. St. John) W.L. Wagner & D.R. Herbst - Kauai bur cucumber

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