PlantPeers
Back to Catalog
No image available
Rosaceae FAMILY

Sorbus japonica

Sorbus japonica

Edibility
2/5
Medicinal
0/5

Safety & Hazards

Although no specific information has been seen, the seed, and other parts of the plant, is likely to contain cyanogenic glycosides. When injested, these compounds break down in the digestive tract to release cyanide. Used in small quantities in both traditional and conventional medicine, this exceedingly poisonous compound has been shown to stimulate respiration, improve digestion, and promote a sense of well-being[1]. It is also claimed by some to be of benefit in the treatment of cancer - though this claim has been largely refuted. In larger concentrations, however, cyanide can cause gasping, weakness, excitement, pupil dilation, spasms, convulsions, coma and respiratory failure leading to death[2]. The levels of toxin can be detected by the level of bitterness:- sweet almonds, for example, contain only very low levels of it and are safe to eat in quantity, whilst bitter almonds (which are used as a flavouring in foods such as marzipan) contain much higher levels and should only be eaten in very small quantities. Great caution should be employed if the taste is moderately to very bitter[PFAF].

Cultivation Details

HabitDeciduous Tree
Growth—

Sorbus japonica is a moderately cold-hardy tree, tolerating temperatures down to around -20°c when dormant. However, it requires hot summers if it is to thrive and will often fail to do well in regions with cool summers, even if the winters are mild. Succeeds in most reasonably good soils in an open sunny position[3]. Tolerates light shade[4], though it fruits better in a sunny position[PFAF]. Plants are susceptible to fireblight[4].

Propagation

Seed - best sown as soon as it is ripe in a cold frame[5, 6]. If you have sufficient seed it can be sown in an outdoor seedbed[5, 6]. Stored seed germinates better if given 2 weeks warm then 14 - 16 weeks cold stratification[7], so sow it as early in the year as possible. Prick out the seedlings into individual pots when they are large enough to handle. Seedlings are very slow to put on top-growth for their first year or two[3], but they are busy building up a good root system. It is best to keep them in pots in a cold frame for their first winter and then plant them out into their permanent positions in late spring. Cite as: Temperate Plants Database, Ken Fern. temperate.theferns.info. 2026-02-21. <temperate.theferns.info/plant/Sorbus+japonica>

Pollinators

Insects

References

  1. [1]Encyclopaedia of Herbs and their Uses. — Bown. D. · Dorling Kindersley, London. · 1995 · ISBN 0-7513-020-31 ↩︎A very well presented and informative book on herbs from around the globe. Plenty in it for both the casual reader and the serious student. Just one main quibble is the silly way of having two separate entries for each plant.
  2. [2]Poisonous Plants of North Carolina — http://www.ces.ncsu.edu/depts/hort/consumer/poison/poison.htm ↩︎An excellent concise but comprehensive guide to toxic plants that grow in N. Carolina. It lists even those plants that are of very low toxicity, including several well-known food plants such as carrots and potatoes.
  3. [3]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.
  4. [4]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.
  5. [5]Propagation of Trees, Shrubs and Conifers. — Sheat. W. G. · MacMillan and Co · 1948 · ISBN - ↩︎A bit dated but a good book on propagation techniques with specific details for a wide range of plants.
  6. [6]Hardy Woody Plants from Seed. — McMillan-Browse. P. · Grower Books · 1985 · ISBN 0-901361-21-6 ↩︎Does not deal with many species but it is very comprehensive on those that it does cover. Not for casual reading.
  7. [7]Seed Manual for Ornamental Trees and Shrubs. — Gordon. A. G. and Rowe. D. C. F. · HMSO; London · 1982 · ISBN 0-11-710152-4 ↩︎Very comprehensive guide to growing trees and shrubs from seed. Not for the casual reader.
  8. [8]Flora of Japan. (English translation) — Ohwi. G. · Smithsonian Institution · 1965 · ISBN - ↩︎The standard work. Brilliant, but not for the casual reader.
  9. [9]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.
  10. [10]Flora of China — Missouri Botanical Garden Press; St. Louis. · 1994 · http://flora.huh.harvard.edu/china/ ↩︎An excellent, comprehensive resource in 25 volumes. In addition to the botanical information the flora also gives basic information on habitat and some uses. An on-line version is also available.
  11. [PFAF]Plants for a Future — pfaf.org ↩︎