Limestone Adderstongue: A Rare and Fascinating Native Fern
Meet the limestone adderstongue (Ophioglossum engelmannii), one of nature’s most understated and elusive native plants. This small perennial fern might not win any beauty contests, but it’s absolutely fascinating for those who appreciate botanical rarities and ecological treasures hiding in plain sight.
What Makes Limestone Adderstongue Special?
Unlike the ferns you might picture with their elaborate, feathery fronds, limestone adderstongue is refreshingly simple. As a member of the adder’s-tongue fern family, it produces just a single, tongue-like leaf that emerges from the ground each growing season. The name limestone gives away its preferred habitat – this little plant has a thing for calcium-rich, alkaline soils typically found around limestone formations.
This native beauty is a true perennial forb, meaning it’s an herbaceous plant that comes back year after year without developing woody stems. Think of it as the minimalist of the fern world – no fuss, no frills, just pure botanical elegance.
Where You’ll Find This Rare Gem
Limestone adderstongue is native to the lower 48 states and has quite an impressive range, spanning across 22 states including Alabama, Arizona, Arkansas, Florida, Georgia, Illinois, Indiana, Kansas, Kentucky, Louisiana, Mississippi, Missouri, Nebraska, New Mexico, North Carolina, Ohio, Oklahoma, Pennsylvania, Tennessee, Texas, Virginia, and West Virginia.
However, don’t let that extensive range fool you – this plant is actually quite rare in many areas. In Alabama, for instance, it holds a rarity status of S2S3, meaning it’s uncommon to moderately rare. This makes every sighting special!
A Plant of Many Habitats
One of the most interesting things about limestone adderstongue is its adaptability to different moisture conditions across its range. Depending on where you are:
- In the Arid West, it’s considered a facultative wetland plant (usually found in wet areas)
- In the Atlantic and Gulf Coastal Plain, Eastern Mountains and Piedmont, Great Plains, and Midwest regions, it’s a facultative upland plant (usually found in drier areas)
This flexibility shows just how adaptable this little fern can be, though it always maintains its preference for limestone-rich soils.
Should You Grow Limestone Adderstongue?
Here’s where we need to have an honest conversation. While limestone adderstongue is undeniably cool from a botanical perspective, it’s not exactly what you’d call a showstopper in the garden. Its small, simple appearance means it won’t provide the dramatic visual impact that most gardeners are looking for.
More importantly, because of its rarity status in many areas, if you do decide to add this plant to your collection, please ensure you’re sourcing it responsibly. Never collect from wild populations – always purchase from reputable native plant nurseries that propagate their stock ethically.
Growing Conditions and Care
If you’re determined to try growing limestone adderstongue, here’s what you need to know:
- Soil: Calcareous, limestone-rich soil with good drainage
- Light: Partial shade to full sun, depending on your region
- Hardiness: Generally suitable for USDA zones 6-9
- Moisture: Varies by location – can handle both wetland and upland conditions
Fair warning: this isn’t a beginner-friendly plant. Limestone adderstongue can be quite finicky about its growing conditions, particularly soil chemistry. It’s definitely more of a specialist plant for dedicated native plant enthusiasts.
The Bottom Line
Limestone adderstongue is a fascinating piece of our native flora that deserves respect and protection. While it might not be the right choice for every garden, it’s an important part of our natural heritage. If you’re interested in truly rare native plants and have the right growing conditions, it could be a unique addition to a specialized native plant collection – just remember to source it responsibly.
For most gardeners looking for attractive, easy-to-grow native ferns, you might want to consider more common species like Christmas fern or lady fern. But for those botanical treasure hunters out there, limestone adderstongue offers the thrill of growing something genuinely rare and special.
