A Tale of Two Ferns: Native and Introduced Hoio in Hawaii’s Culinary Landscape
Posted on Jul. 1, 2025 / Native Species / Subscribe 0
By: Chuck Chimera
Almost every Sunday, my family and I head to the farmers market to sample the rich diversity of foods offered by vendors with ancestry from across the globe—a true reflection of the cultural and culinary melting pot that is Hawai‘i. From savory Korean barbecue to fragrant Thai curry, Colombian patacones to wood-fired Italian pizza, and freshly fried lumpia, there’s something for everyone. But if I want to grab one of my local favorites, I know we have to get there early—before it sells out. That favorite is pohole (also known as hōʻiʻo) salad, freshly harvested from a Kukuihaele farm. It’s the perfect complement to our midday snack of Waipi‘o poi and shoyu ‘ahi poke.
As a former botanist with the National Park Service, I’ve encountered the native Hawaiian hōʻiʻo fern many times in the wild. Yet that familiarity doesn’t diminish my enjoyment of the version typically sold at markets today. Interestingly, the fern commonly used in hōʻiʻo salad isn't native to Hawai‘i at all. This culinary staple is actually an introduced species. Knowing this often makes me wonder how many people realize that the same Hawaiian name is used for two very different ferns—one endemic, one introduced. Though similar in appearance and use, their stories diverge in ways that reflect both the resilience of native ecosystems and the adaptability of new arrivals.
The Native Hōʻiʻo: Diplazium sandwichianum
Also called pohole on Maui, the native hōʻiʻo (Diplazium sandwichianum) is deeply rooted in both the Hawaiian landscape and traditional culture. Its species name, sandwichianum, is a nod to the Islands’ former name, the Sandwich Islands. These impressive ferns grow in lush colonies with arching fronds that can stretch over five feet long. You’ll find them carpeting the understory of mesic to wet forests across all the main Hawaiian Islands, thriving from elevations as low as 300 feet to over 6,000 feet, but typically only within protected or more intact native forests.
For generations, Hawaiians have valued hōʻiʻo as a food source. The tender young shoots—called fiddleheads or crosiers—were eaten raw or with poi and freshwater ‘ōpae (shrimp). This tradition lives on today, with wild shoots still gathered for salads. The fern’s cultural significance is memorialized in an ʻōlelo noʻeau (Hawaiian proverb):
“Ka i‘a lauoho loloa ka ‘āina” – The long-haired fish of the land.
Here, the fronds of hōʻiʻo are poetically likened to the long hair of the plants, a staple as essential as fish in the traditional Hawaiian diet (Mary Kawena Pukui, ʻŌlelo Noʻeau, #1361).
Figure 1. Native mesic forest with a carpet of the native hōʻiʻo (Diplazium sandwichianum) in the understory.
The Introduced Hōʻiʻo: Diplazium esculentum
By contrast, the vegetable fern (Diplazium esculentum)—also called hōʻiʻo in Hawai‘i—comes from tropical Asia. It was likely introduced as a food plant in the late 19th or early 20th century and was first recorded on Kaua‘i in 1910. Since then, it has naturalized across the larger islands, forming broad, often untidy stands in wet areas.
Unlike the forest-dwelling native fern, D. esculentum prefers open, disturbed areas with moist soil. It thrives along streams, in lowland valleys, and even in gardens or sheltered, irrigated spots on the drier leeward side. Its resilience and prolific growth have helped it spread widely across the islands. Although it may be considered weedy or invasive in some locations, it typically occurs in areas already dominated by other non-native vegetation.
In both its native and introduced ranges, D. esculentum is a popular vegetable. In Hawai‘i, its fiddleheads are served raw in salads, sautéed, stir-fried, or stewed—commonly paired with garlic, pork, shrimp, or salted salmon. You’ll often find bunches for sale at farmers markets or gathered from the wild. Its popularity even led to USDA approval for export to the continental U.S. in 1991.
Figure 2. Open field dominated by the introduced hōʻiʻo (Diplazium sandwichianum).
Shared Names, Divergent Origins
The presence of two edible ferns both called hōʻiʻo or pohole can lead to confusion. These traditional names properly refer to Diplazium sandwichianum, yet they are commonly used to describe the more readily available D. esculentum. Even the Japanese name warabi is sometimes mistakenly applied to D. esculentum.
Visually, careful observation of the fronds and sori (spore structures) can help differentiate the two:
- D. sandwichianum has free veins and short, linear sori.
- D. esculentum features anastomosing (netlike) veins and sori arranged in a distinctive herringbone pattern.
Their size and frond structure also differ:
- D. sandwichianum has narrow ultimate segments (4–6 mm wide).
- D. esculentum has broader segments (0.5–2 cm wide and up to 8 cm long).
Figure 3. Sori and ultimate segments of the native (left) and introduced (right) hōʻiʻo ferns.
Conclusion: Two Ferns, Two Stories
Both Diplazium sandwichianum and Diplazium esculentum enrich Hawai‘i’s culinary landscape with their crisp, edible fiddleheads. Yet they tell different stories: one of a native species integral to Hawaiian ecosystems and culture, and one of an adaptable newcomer that found a place in modern kitchens and wet valleys alike.
As you enjoy your next hōʻiʻo salad, whether from the forest or the farmers market, take a moment to consider the lineage behind those fronds—and the layered stories that make Hawai‘i’s biodiversity, and its food, so unique.
Please visit the Plant Pono website (https://plantpono.org/) for more information on native, introduced and invasive plants in the Hawaiian landscape.
Chuck Chimera is currently chained to a computer as a weed risk assessment specialist with the Hawaii Invasive Species Council but was a free-range field botanist in a previous life.
0 Comments