Non-native Plants

Steyermark’s Trimezia

Trimezia steyermarkii

USDA symbol: TRST3

perennial forb

Puerto Rico: non-native, naturalized

Meet Steyermark’s trimezia (Trimezia steyermarkii), a perennial plant that’s something of an enigma in the gardening world. While many gardeners are familiar with popular flowering perennials, this particular species flies under the radar, and honestly, that’s part of what makes it intriguing. Steyermark’s trimezia is a perennial forb, which is ...

Steyermark’s Trimezia: A Lesser-Known Perennial with an Air of Mystery

Meet Steyermark’s trimezia (Trimezia steyermarkii), a perennial plant that’s something of an enigma in the gardening world. While many gardeners are familiar with popular flowering perennials, this particular species flies under the radar, and honestly, that’s part of what makes it intriguing.

What Exactly Is Steyermark’s Trimezia?

Steyermark’s trimezia is a perennial forb, which is just a fancy way of saying it’s a non-woody plant that comes back year after year. As a forb, it lacks the significant woody tissue that you’d find in shrubs or trees, instead maintaining its perennating buds at or below ground level – nature’s way of ensuring it survives to bloom another season.

This plant belongs to the iris family and has been known by the synonym Trimezia martinicensis in some botanical circles, though that name has been misapplied to this species.

Where Does It Call Home?

Here’s where things get interesting: Steyermark’s trimezia isn’t actually native to Puerto Rico, where it currently grows, but it has established itself there as a naturalized species. It reproduces on its own in the wild and has shown it can persist without human intervention – essentially, it’s made itself at home in Puerto Rican landscapes.

  • Species observed
  • No observations

Should You Consider Growing It?

This is where we hit a bit of a gardening conundrum. Steyermark’s trimezia falls into that category of plants that are neither vilified as invasive nor celebrated as native treasures. Since its invasive status is unknown and it’s not listed as noxious, there’s no red flag preventing you from growing it – but there’s also limited information about how to do so successfully.

If you’re drawn to unusual plants and don’t mind a bit of gardening detective work, this could be an interesting addition to your collection. However, if you’re looking for reliable, well-documented plants with known care requirements, you might want to consider better-studied alternatives.

The Challenge of Growing Steyermark’s Trimezia

Here’s the honest truth: specific growing information for Steyermark’s trimezia is remarkably scarce. We know it’s a perennial that has managed to establish itself in Puerto Rico’s climate, which suggests it can handle tropical or subtropical conditions, but beyond that, details about its preferences for soil, water, light, and care requirements are limited.

Consider Native Alternatives

Since Steyermark’s trimezia isn’t native to most gardening areas and information about it is limited, you might want to explore native iris family members or similar perennial forbs that are better suited to your local ecosystem. Native plants typically:

  • Require less maintenance once established
  • Support local wildlife and pollinators
  • Are adapted to local climate conditions
  • Come with well-documented growing guides

The Bottom Line

Steyermark’s trimezia represents one of those botanical mysteries that might appeal to adventurous gardeners willing to experiment. While it’s not problematic enough to avoid entirely, the lack of available growing information makes it a bit of a gamble for most home gardeners.

If you do decide to try growing it, approach it as you would other members of the iris family and be prepared to learn through trial and observation. And remember – sometimes the most rewarding garden discoveries come from the plants that make us work a little harder to understand them.

Trimezia steyermarkii is also known as...

Often we refer to plants by their common names. When shopping for plants the scientific name is the best way to positively identify the plant species you desire. But some plants have more than one name! While it doesn't happen often, nurseries might display one name while you're searching for another. Trimezia steyermarkii is also known as:

Trimezia martinicensis auct. non | USDA symbol: TRMA22

Why do some plants have more than one name? Over time plant species may be renamed for a few reasons:

  1. Botanists in different regions named the same plant without knowing it had already been classified.
  2. A species was reclassified after scientific advances in, for example, DNA analysis.
  3. Slight variations within a species are sometimes mistakenly identified as entirely new species.

Classification

Group: Monocot
Kingdom: Plantae - Plants
Subkingdom: Tracheobionta - Vascular plants
Superdivision: Spermatophyta - Seed plants
Division: Magnoliophyta - Flowering plants
Class: Liliopsida - Monocotyledons
Subclass: Liliidae
Order: Liliales
Family: Iridaceae Juss. - Iris family
Genus: Trimezia Salisb. ex Herb. - trimezia

Species: Trimezia steyermarkii R.C. Foster - Steyermark's trimezia

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