North America Native Plant

Darkgreen Maiden Fern

Botanical name: Thelypteris poiteana

USDA symbol: THPO5

Life cycle: perennial

Habit: forb

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

Synonyms: Dryopteris poiteana (Bory) Urb. (DRPO4)   

Darkgreen Maiden Fern: A Caribbean Native Worth Knowing If you’ve ever wandered through the lush landscapes of Puerto Rico or the U.S. Virgin Islands, you might have encountered the darkgreen maiden fern (Thelypteris poiteana) without even realizing it. This perennial fern is a true Caribbean native that adds a touch ...

Darkgreen Maiden Fern: A Caribbean Native Worth Knowing

If you’ve ever wandered through the lush landscapes of Puerto Rico or the U.S. Virgin Islands, you might have encountered the darkgreen maiden fern (Thelypteris poiteana) without even realizing it. This perennial fern is a true Caribbean native that adds a touch of tropical elegance to its natural habitat.

What Makes This Fern Special?

The darkgreen maiden fern belongs to the Thelypteris genus, a group of ferns known for their delicate fronds and adaptable nature. As its name suggests, this fern is characterized by its notably dark green foliage, which sets it apart from its lighter-colored cousins. You might also see it referenced by its botanical synonym, Dryopteris poiteana, in older botanical literature.

Where You’ll Find It

This charming fern calls the Caribbean home, specifically thriving in Puerto Rico and the U.S. Virgin Islands. It’s perfectly adapted to the warm, humid conditions of these tropical islands, making it a true regional specialty.

A Wetland Wanderer

One of the most interesting aspects of the darkgreen maiden fern is its flexible relationship with water. It’s classified as facultative when it comes to wetland conditions, which is just a fancy way of saying it’s equally happy in wet spots and drier areas. This adaptability makes it quite the survivor in the varied Caribbean landscape!

Garden Benefits and Considerations

As a native Caribbean species, this fern plays an important role in local ecosystems. While it may not attract pollinators like flowering plants do (ferns reproduce through spores, not flowers), it contributes to the overall biodiversity and natural beauty of tropical gardens and landscapes.

For gardeners in tropical zones (likely USDA zones 10-11), incorporating native ferns like the darkgreen maiden fern can:

  • Add authentic local character to your landscape
  • Support regional biodiversity
  • Provide low-maintenance greenery that’s naturally adapted to local conditions
  • Create attractive ground cover in both sunny and partially shaded areas

The Reality Check

Here’s where we need to be honest: specific growing information for Thelypteris poiteana is quite limited in readily available sources. This isn’t uncommon for regional native species that haven’t been widely cultivated outside their natural range. If you’re lucky enough to garden in Puerto Rico or the U.S. Virgin Islands and are interested in this particular fern, your best bet would be to:

  • Contact local native plant societies or botanical gardens
  • Consult with regional horticulturists familiar with Caribbean ferns
  • Look for it in its natural habitat to observe its preferred growing conditions

Bottom Line

The darkgreen maiden fern represents the unique beauty of Caribbean flora. While it may not be the easiest fern to find information about or source for your garden, it’s a wonderful example of the specialized plant life that makes tropical islands so botanically fascinating. For most gardeners outside its native range, appreciating this fern might mean simply learning about the incredible diversity of plants that call the Caribbean home.

If you’re gardening in similar tropical conditions and looking for ferns to add to your landscape, consider reaching out to local experts who can guide you toward both this species and other native alternatives that will thrive in your specific microclimate.

Wetland Status

The rule of seasoned gardeners and landscapers is to choose the "right plant for the right place" matching plants to their ideal growing conditions, so they'll thrive with less work and fewer inputs. But the simplicity of this catchphrase conceals how tricky plant selection is. While tags list watering requirements, there's more to the story.

Knowing a plant's wetland status can simplify the process by revealing the interaction between plants, water, and soil. Surprisingly, many popular landscape plants are wetland species! And what may be a wetland plant in one area, in another it might thrive in drier conditions. Also, it helps you make smarter gardening choices and grow healthy plants with less care and feeding, saving you time, frustration, and money while producing an attractive garden with greater ecological benefits.

Regions
Status
Moisture Conditions

Caribbean

FAC

Facultative - Plants with this status can occur in wetlands and non-wetlands

Darkgreen Maiden Fern

Classification

Group

Fern

Kingdom

Plantae - Plants

Subkingdom

Tracheobionta - Vascular plants

Superdivision
Division

Pteridophyta - Ferns

Subdivision
Class

Filicopsida

Subclass
Order

Polypodiales

Family

Thelypteridaceae Ching ex Pic. Serm. - Marsh Fern family

Genus

Thelypteris Schmidel - maiden fern

Species

Thelypteris poiteana (Bory) Proctor - darkgreen maiden fern

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