Plate 1 figs. a–h · 8 separate observations
Every figure is a research-grade observation under CC0, CC BY or CC BY-SA, rehosted with the photographer’s name, the licence and the observation it came from. Photographs under a NonCommercial licence are excluded from this site and are never stored, which costs us a great many pictures and is not negotiable.
Native range 14 botanical countries
| Region | TDWG code | Continent |
|---|---|---|
| China North-Central | CHN | ASIA-TEMPERATE |
| China South-Central | CHC | |
| China Southeast | CHS | |
| Japan | JAP | |
| Korea | KOR | |
| Nansei-shoto | NNS | |
| Ogasawara-shoto | OGA | |
| Taiwan | TAI | |
| Bangladesh | BAN | ASIA-TROPICAL |
| Jawa | JAW | |
| Lesser Sunda Is. | LSI | |
| Myanmar | MYA | |
| Philippines | PHI | |
| Vietnam | VIE |
Not drawn on the map: Ogasawara-shoto. We hold no public-domain boundary for this region, so it is listed rather than guessed at.
Region boundaries approximated from Natural Earth (public domain) and mapped to TDWG World Geographical Scheme for Recording Plant Distributions (WGSRPD) level-3 botanical countries (Brummitt 2001). Indicative, not the official WGSRPD geometry.
Where it actually grows measured, from 880 observations
| Condition | 5th percentile | Median | 95th percentile |
|---|---|---|---|
| Coldest month, mean daily low | 0.4 °C | 11.7 °C | 15.1 °C |
| Warmest month, mean daily high | 22.8 °C | 29.1 °C | 30.6 °C |
| Annual rainfall | 1,346 mm | 2,580 mm | 3,987 mm |
| Rainfall in the driest quarter | 101 mm | 181 mm | 693 mm |
It is found where winters are cool but frost is light or absent. This is not care advice and it is not a forecast. It is a measurement: we sampled the climate at every one of the 880 research-grade observations of Onychium japonicum that carry a coordinate, and this is the range those places actually span. The 5th and 95th percentiles are used rather than the minimum and maximum, because a single cultivated specimen in a heated conservatory should not widen a tropical plant's range to the Arctic.
This is not a hardiness zone. A USDA zone is the average annual extreme minimum temperature. The figure above is the mean daily minimum of the coldest month, which is a different quantity and is typically far warmer. Reading one as the other would place a plant several zones too warm, so we do not publish a hardiness zone, because we do not have one.
Also published as 12 synonyms
A synonym is not an error. It is a record of botanists disagreeing, in print, about where this plant belongs. Each of these was somebody’s considered answer.
- Asplenium japonicum (Thunb.) Kunze
- Asplenium swartzianum Kunze
- Caenopteris japonica (Thunb.) Thunb.
- Caenopteris japonica Willd.
- Cryptogramma japonica (Thunb.) Prantl
- Darea japonica (Thunb.) Willd.
- Onychium carvifolium Fée
- Onychium chinense Fée
- Onychium japonicum f. echizenense Yo.Saito & Y.Yoshim.
- Onychium japonicum var. japonicum
- Pteris japonica (Thunb.) Mett.
- Trichomanes japonicum Thunb.
Sourcesevery claim on this page
- World Flora Online Plant List. accepted name, authority, classification. CC0. Retrieved 2026-07-12.
- iNaturalist. photographs and flowering annotations, CC0 / CC BY / CC BY-SA only. per photograph. Retrieved 2026-06-27.
- Kew, World Checklist of Vascular Plants (WCVP v16). native distribution by TDWG level-3 botanical country, and life form. CC BY 3.0. Retrieved 2026-06-04.
We publish what we can source and we say so when we cannot. This page has no care advice and no toxicity claim, because we do not yet have those from a source we can cite.