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Araceae FAMILY

Oplopanax japonicus

Oplopanax japonicus

Edibility
2/5
Medicinal
1/5

Safety & Hazards

The plant is densely armed with spikes and these spikes are irritant[1]. Although no specific mention has been seen for this plant, it belongs to a genus where the species are usually rich in calcium oxylate, this is toxic and if consumed makes the mouth and digestive tract feel as though hundreds of needles are being stuck into it. However, calcium oxylate is easily destroyed by thoroughly cooking or drying the plant.

Cultivation Details

HabitDeciduous Shrub
Growth—

Requires a cool moist soil[2, 1]. Prefers a position in light shade[3]. Prefers dense shade and is probably best if grown in moist woodland[4, 2]. Tolerates maritime exposure[1]. (Rather a strange report for a plant that needs to be grown in dense shade[PFAF]) A very hardy plant, tolerating temperatures down to at least -15°c, but the young shoots in spring can be damaged by late frosts[2, 1]. It is therefore best not grown in a frost pocket[3]. This species used to be included in O. horridus as the Japanese form of that species, but it has recently (1991) been recognised as a distinct species[1]. A very ornamental plant, but it is densely armed with spikes[5]. It transplants easily and also tolerates pruning[1]. The leaves and stems are excessively spiny[3].

Propagation

Seed - best sown in a cold frame as soon as it is ripe in the autumn[1]. When they are large enough to handle, prick the seedlings out into individual pots and grow them on in the greenhouse for at least their first winter. Plant them out into their permanent positions in late spring or early summer, after the last expected frosts. Division of suckers in the dormant season. Root cuttings in a greenhouse in the winter[6]. Cite as: Temperate Plants Database, Ken Fern. temperate.theferns.info. 2026-02-21. <temperate.theferns.info/plant/Oplopanax+japonicus>

Pollinators

Data unavailable

References

  1. [1]The New RHS Dictionary of Gardening. 1992. — Huxley. A. · MacMillan Press · 1992 · ISBN 0-333-47494-5 ↩︎Excellent and very comprehensive, though it contains a number of silly mistakes. Readable yet also very detailed.
  2. [2]Trees and Shrubs Hardy in Great Britain. Vol 1 - 4 and Supplement. — Bean. W. · Murray · 1981 · ISBN - ↩︎A classic with a wealth of information on the plants, but poor on pictures.
  3. [3]Ornamental Shrubs, Climbers and Bamboos. — Thomas. G. S. · Murray · 1992 · ISBN 0-7195-5043-2 ↩︎Contains a wide range of plants with a brief description, mainly of their ornamental value but also usually of cultivation details and varieties.
  4. [4]RHS Dictionary of Plants plus Supplement. 1956 — F. Chittendon. · Oxford University Press · 1951 · ISBN - ↩︎Comprehensive listing of species and how to grow them. Somewhat outdated, it has been replaced in 1992 by a new dictionary (see [ 200 ]).
  5. [5]Vascular Plants of the Pacific Northwest. — Hitchcock. C. L. · University of Washington Press · 1955 · ISBN - ↩︎A standard flora for Western N. America with lots of information on habitat etc. Five large volumes, it is not for the casual reader.
  6. [6]The RHS Gardener's Encyclopedia of Plants and Flowers — Brickell. C. · Dorling Kindersley Publishers Ltd. · 1990 · ISBN 0-86318-386-7 ↩︎Excellent range of photographs, some cultivation details but very little information on plant uses.
  7. [7]Plants in British Columbian Indian Technology. — Turner. N. J. · British Columbia Provincial Museum · 1979 · ISBN 0-7718-8117-7 ↩︎Excellent and readable guide.
  8. [8]Dictionary of Economic Plants. — Uphof. J. C. Th. · Weinheim · 1959 · ISBN - ↩︎An excellent and very comprehensive guide but it only gives very short descriptions of the uses without any details of how to utilize the plants. Not for the casual reader.
  9. [9]A Dictionary of Plants Used by Man. — Usher. G. · Constable · 1974 · ISBN 0094579202 ↩︎Forget the sexist title, this is one of the best books on the subject. Lists a very extensive range of useful plants from around the world with very brief details of the uses. Not for the casual reader.
  10. [10]Tanaka's Cyclopedia of Edible Plants of the World. — Tanaka. T. & Nakao S. · Keigaku Publishing; Tokyo · 1976 · ISBN - ↩︎The most comprehensive list of edible plants I've come across. Only the briefest entry for each species, though, and some of the entries are more than a little dubious. Not for the casual reader.
  11. [11]The Dictionary of Useful Plants. — Coon. N. · Rodale Press · 1975 · ISBN 0-87857-090-x ↩︎Interesting reading but short on detail.
  12. [12]Discovering Wild Plants - Alaska, W. Canada and the Northwest. — Schofield. J. J. · Alaska Northwest Books; Alaska · 2003 · ISBN 0882403699 ↩︎A nice guide to some useful plants in that area.
  13. [13]Food Plants of the N. American Indians. — Yanovsky. E. · U.S. Depf of Agriculture. · ISBN - ↩︎A comprehensive but very terse guide. Not for the casual reader.
  14. [PFAF]Plants for a Future — pfaf.org ↩︎