PlantPeers
Back to Catalog
No image available
Ericaceae FAMILY

Pieris japonica

Pieris japonica

Edibility
0/5
Medicinal
0/5

Safety & Hazards

The plant is poisonous[1]. All parts of the plant (including the leaves, flowers and pollen) contain greater or lesser amounts of the toxic compound andromedotoxin (also known as grayanotoxin) [2]. Rarely lethal to humans (and used medicinally in some herbal disciplines), this compound causes dose-dependant overstimulation of the central nervous system with symptoms including various cardiovascular effects (mainly low blood pressure and cardiac rhythm disorders); nausea and vomiting; and a change in consciousness. The effects commence shortly after ingestion and last around two days. These effects are also transferred to honey made from the nectar of the flowers. In some parts of the world bees are used to deliberately produce a honey rich in andromedotoxin which is then eaten for its supposed medicinal, hallucinogenic and aphrodisiac effects. In contrast to humans, many other creatures are more susceptible to the toxin and it has sometimes proved lethal to grazing animals and household pets. Some forms of honeybees are also killed by the toxin (resistant forms of the bee are used for honey production). Bumblebees are not affected, however, and are also more efficient in pollinating rhododendron flowers, so one theory is that the toxin is produced by the plant in order to favour the bumblebee and improve fertilization rates[2].

Cultivation Details

HabitEvergreen Shrub
Growth—

Easily grown in a moist acid peaty soil but it requires a sheltered position because the young growth is easily damaged by frost[3, 4, 5, 6]. Plants grow best with a western exposure so that they are protected from morning frosts[3]. They flower more freely when grown in a sunny position[6]. Best grown in shade or semi-shade[7], they grow well in a woodland garden[6]. Dormant plants are hardy to about -20°c[5]. A very ornamental plant, there are many named varieties[4, 6]. The flowers are delicately scented[8]. A slow growing plant[6]. Plants sometimes succumb to an incurable fungal infection[6]. Plants in this genus are notably resistant to honey fungus[6].

Propagation

Seed - surface sow in the spring on a fine moss peat. Keep the compost moist and place the pot in a shaded part of the greenhouse[6]. When they are large enough to handle, prick the seedlings out into individual pots and grow them on in a shady part of 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. Cuttings of short side branches with a heel, mid summer to early autumn in a frame[9]. Layering. Offsets. Cite as: Temperate Plants Database, Ken Fern. temperate.theferns.info. 2026-02-21. <temperate.theferns.info/plant/Pieris+japonica>

Pollinators

Data unavailable

References

  1. [1]Atlas of Medicinal Plants. — Kariyone. T. · Nihon Rinshosha; Osaka · 1973 ↩︎A good Japanese herbal.
  2. [2]Grayanotoxin Poisoning: ‘Mad Honey Disease’ and Beyond — Jansen S.A. et al · 2012 · https://doi.org/10.1007/s12012-012-9162-2 ↩︎An in-depth review of the literature on the toxic effects of a toxin widely found in the family Ericaceae
  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]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.
  5. [5]Shrubs. — Phillips. R. & Rix. M. · Pan Books · 1989 · ISBN 0-330-30258-2 ↩︎Excellent photographs and a terse description of 1,900 species and cultivars.
  6. [6]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.
  7. [7]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.
  8. [8]Scented Flora of the World. — Genders. R. · Robert Hale. London. · 1994 · ISBN 0-7090-5440-8 ↩︎An excellent, comprehensive book on scented plants giving a few other plant uses and brief cultivation details. There are no illustrations.
  9. [9]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 ]).
  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.