Cordillera Maiden Fern: A Critically Endangered Puerto Rican Treasure
Meet the cordillera maiden fern (Thelypteris inabonensis), one of Puerto Rico’s rarest botanical gems. This extraordinary fern isn’t just uncommon—it’s critically imperiled, making it one of the most endangered plants you’ll probably never see in a typical garden center.
What Makes This Fern Special?
The cordillera maiden fern belongs to the maiden fern family, a group known for their delicate, lacy fronds. As a perennial species, this fern would theoretically come back year after year if given the right conditions. However, finding those right conditions—and the plant itself—is where things get tricky.
Where Does It Come From?
This remarkable fern is native exclusively to Puerto Rico, where it has carved out a very specific niche in the island’s diverse ecosystem. Unfortunately, its geographical distribution is extremely limited within Puerto Rico itself, contributing to its precarious conservation status.
The Reality Check: Why This Isn’t Your Average Garden Fern
Here’s where we need to have a serious conversation about rarity. The cordillera maiden fern has a Global Conservation Status of S1, which translates to Critically Imperiled. In plain English? This means there are typically only 5 or fewer known locations where this fern exists, with fewer than 1,000 individual plants remaining in the wild. In the United States, it’s classified as Endangered.
What does this mean for gardeners? Simply put, this isn’t a plant you can or should casually add to your wish list.
Should You Try to Grow It?
If you’re thinking about growing the cordillera maiden fern, proceed with extreme caution and responsibility. Here are the key considerations:
- Source responsibly: Only obtain plants from reputable conservation programs or botanical institutions working on species recovery
- Never collect from the wild: Taking plants from their natural habitat could push this species closer to extinction
- Support conservation efforts: Consider donating to organizations working to protect Puerto Rican native plants instead
Growing Conditions and Care
While specific growing requirements for this rare fern aren’t well-documented (partly due to its scarcity), most Thelypteris species generally prefer:
- Partial to full shade conditions
- Consistently moist, well-draining soil
- High humidity environments
- Protection from strong winds
Given its Puerto Rican origins, the cordillera maiden fern would likely thrive in warm, tropical to subtropical conditions, though specific USDA hardiness zone information isn’t readily available.
Alternative Native Ferns to Consider
Instead of seeking out this critically endangered species, consider these more readily available native fern alternatives for your region:
- Christmas fern (Polystichum acrostichoides) for temperate regions
- Royal fern (Osmunda regalis) for wetland gardens
- Lady fern (Athyrium filix-femina) for woodland settings
The Bigger Picture
The cordillera maiden fern serves as a powerful reminder of how precious and fragile our native plant heritage can be. While most of us will never have the opportunity to grow this particular species, we can all play a role in supporting plant conservation by:
- Choosing native plants for our gardens
- Supporting botanical gardens and conservation organizations
- Learning about and protecting rare plants in our own regions
Sometimes the most beautiful thing we can do for a rare plant is simply to appreciate it from afar and work to ensure it survives for future generations to discover.
