Old World Adderstongue: A Distinctive Fern for Shade Gardens
Meet the Old World adderstongue (Ophioglossum pendulum pendulum), also known by its Hawaiian name puapuamoa. This unique fern might not win any beauty contests, but it certainly wins points for being wonderfully weird. If you’re looking for something different to add to your shade garden, this little oddball might just be the conversation starter you never knew you needed.
What Makes This Fern Special?
The Old World adderstongue belongs to a fascinating group of primitive ferns that look nothing like the typical frilly ferns you might expect. Instead of the classic feathery fronds, this perennial forb produces simple, tongue-like leaves with a distinctive fertile spike that gives it its adderstongue common name. It’s like nature decided to create a fern that looks more like a small succulent plant – quirky and unexpected.
Where Does It Come From?
This fern is a world traveler from the Old World tropics, originally native to Africa, Asia, and Pacific islands. In the United States, it has established itself in Florida and Hawaii, where it reproduces on its own and persists in the wild. While it’s not native to these areas, it has found a comfortable home in these warm, humid climates.
Is It Right for Your Garden?
The Old World adderstongue can be an interesting addition to the right garden setting, but it’s definitely not for everyone. Here’s what to consider:
The Good
- Unique appearance that’s sure to spark curiosity
- Low-maintenance once established
- Thrives in shady spots where other plants struggle
- Perennial growth means it comes back year after year
The Not-So-Good
- Very subtle aesthetic appeal – not a showstopper
- Limited wildlife benefits since ferns don’t produce flowers
- Not native, so it won’t support local ecosystems as well as indigenous plants
Growing Conditions and Care
If you decide to give this unusual fern a try, here’s what it needs to thrive:
Climate Requirements
- USDA hardiness zones 9-11
- Warm, humid conditions
- Protection from frost
Site Preferences
- Shade to partial shade
- Moist, well-draining soil rich in organic matter
- Consistent moisture without waterlogging
- Protected from strong winds
Care Tips
- Water regularly during dry periods
- Mulch around plants to retain moisture
- Remove any dead or damaged fronds
- Fertilize lightly with organic matter in spring
Garden Design Ideas
The Old World adderstongue works best in naturalistic shade gardens or tropical-themed landscapes. Its simple form can provide textural contrast among more ornate plants, and it’s particularly at home in:
- Understory plantings beneath trees
- Shaded rock gardens
- Tropical or subtropical landscape designs
- Collections of unusual or primitive plants
Consider Native Alternatives
While the Old World adderstongue isn’t considered invasive, choosing native plants is always beneficial for local wildlife and ecosystems. Consider these native alternatives that thrive in similar conditions:
- Native Ophioglossum species in your region
- Local woodland ferns
- Indigenous shade-loving perennials
The Bottom Line
The Old World adderstongue is definitely a niche plant for gardeners who appreciate botanical curiosities over flashy flowers. If you’re drawn to unusual plants and have the right growing conditions, it can be an interesting addition to your shade garden. Just remember that while it’s not problematic, native plants will always be the better choice for supporting local wildlife and maintaining ecological balance.
Whether you choose to grow this quirky fern or opt for native alternatives, the most important thing is creating a garden that brings you joy and connects you with the natural world around you.
