North America Native Plant

Tropical Buttonweed

Botanical name: Diodia sarmentosa

USDA symbol: DISA8

Life cycle: perennial

Habit: vine

Native status: Native to Puerto Rico âš˜ Native to the U.S. Virgin Islands  

Tropical Buttonweed: A Lesser-Known Native for Caribbean Gardens If you’re gardening in Puerto Rico or the U.S. Virgin Islands and looking to support local ecosystems, you might want to get acquainted with tropical buttonweed. This unassuming native plant goes by the scientific name Diodia sarmentosa, and while it may not ...

Tropical Buttonweed: A Lesser-Known Native for Caribbean Gardens

If you’re gardening in Puerto Rico or the U.S. Virgin Islands and looking to support local ecosystems, you might want to get acquainted with tropical buttonweed. This unassuming native plant goes by the scientific name Diodia sarmentosa, and while it may not be the showiest addition to your garden, it represents an authentic piece of Caribbean flora.

What Is Tropical Buttonweed?

Tropical buttonweed is a perennial herb that belongs to the coffee family (Rubiaceae). Don’t expect towering heights or woody stems from this little guy – it’s what botanists call a forb, which is just a fancy way of saying it’s a soft-stemmed plant that comes back year after year. Think of it as the quiet, dependable friend of the plant world.

Where Does It Call Home?

This native beauty is found naturally in Puerto Rico and the U.S. Virgin Islands, where it has adapted to the tropical climate over countless generations. Being a true local, it’s perfectly suited to the unique growing conditions of these Caribbean islands.

Should You Plant Tropical Buttonweed?

Here’s where things get a bit tricky – tropical buttonweed is one of those plants that keeps its secrets well. While we know it’s a native species (which is always a good thing for local wildlife and ecosystem health), detailed information about its specific benefits and growing requirements is surprisingly scarce in gardening literature.

However, there are some good reasons to consider it:

  • It’s a true native, meaning it naturally belongs in Caribbean landscapes
  • As a perennial, it offers long-term garden value
  • Native plants typically require less water and maintenance once established
  • It likely supports local insects and wildlife in ways we’re still discovering

Growing Tropical Buttonweed

Unfortunately, specific growing guidance for tropical buttonweed is limited, which means you might be venturing into somewhat uncharted gardening territory. Based on its native habitat in Puerto Rico and the Virgin Islands, here’s what we can reasonably assume:

  • Climate zones: Likely thrives in USDA zones 10-11, matching its tropical native range
  • Growing conditions: Probably prefers the warm, humid conditions typical of Caribbean climates
  • Maintenance: Being a native, it should be relatively low-maintenance once established

The Bottom Line

Tropical buttonweed presents an interesting case for the adventurous native plant gardener. While it may not come with a detailed instruction manual, choosing native species is generally a win for both your garden and the local environment. If you can find this plant from a reputable native plant source in Puerto Rico or the Virgin Islands, it could be a unique addition to a naturalized garden or native plant collection.

Just remember – since information is limited, you’ll be part plant detective and part pioneer gardener. Keep notes on what works, and you might just help fill in the knowledge gaps for future tropical buttonweed enthusiasts!

If you’re looking for well-documented native alternatives with similar growth habits, consider exploring other native Caribbean herbs and forbs that might offer more established growing guidance while still supporting your local ecosystem.

Tropical Buttonweed

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

Diodia L. - buttonweed

Species

Diodia sarmentosa Sw. - tropical buttonweed

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