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Cupressaceae FAMILY Least Concern

Juniperus communis

Juniperus communis

Edibility
3/5
Medicinal
3/5

Safety & Hazards

The essential oil in this plant contains thujone[1]. Thujone is a GABA receptor antagonist which allows neurons to fire more easily. In larger doses this can cause muscle spasms and convulsions, and can also be toxic to brain, kidney, and liver cells. There has been a lot of negative press regarding thujone, particularly in the mid 19th century when thujone was reported to be more dangerous than alcohol - since shown to be exaggerated; and reports in the 1970’s that it might have a similar effect on the brain to THC (found in cannabis) – since found to be incorrect. Thujone is probably best known for its use in the alcoholic drink ‘Absinthe’. It is also found in the essential oils of many other plants that are used in herbal medicines and foods, including Arborvitae (Thuja species), some Junipers (Juniperus species), Wormwoods (especially Artemisia absinthium) and Sage (Salvia officinalis). There are some legal restrictions in various countries on the quantity of thujone that can be added to foods and drinks and these vary between countries. Side effects from consuming thujone can include sleeplessness and anxiety but, unless the pure essential oil is used, the quantity of thujone found in plants is well within safety levels. Pregnant women, however, may be advised to restrict their use of thujone-containing plants. Juniper should not be used internally in any quantities by pregnant women[2, 3].

Cultivation Details

HabitEvergreen Shrub
GrowthSlow

Juniperus communis is a very cold-hardy plant, able to tolerate temperatures down to around -40°c when fully dormant. However, although the fully dormant plant is very cold-tolerant, the young growth in spring can be damaged by late frosts. An easily grown plant, it succeeds in hot dry soils and in poor soils. This species seems very indifferent to soil type and occurs in dry sand, chalk downs, and loose (dolomitic) scree, as well as in acidic peat, with low or fluctuating ground water levels[4]. Succeeds in most soils so long as they are well drained[5], preferring a neutral or slightly alkaline soil. Does well in chalky soils[6]. Grows well in heavy clay soils. Tolerates a pH range from 4 to 8[5]. Succeeds in light woodland but dislikes heavy shade[5]. Established plants are very tolerant of drought[5]. All parts of the plant are very aromatic[7]. Juniper is a very polymorphic species that has a long history of culinary and medicinal use[8]. It is frequently grown in the ornamental and herb garden, there is a huge range of cultivars of widely diverse habits[9, 10]. At least some forms tolerate maritime exposure[5], there is a thriving colony in an exposed position at Land's End in Cornwall[10]. The fruits take 2 - 3 years to ripen on the plant[9]. Plants are usually very slow growing, often only a few centimetres a year[5]. Resists honey fungus[11]. Plants are sometimes attacked by a rust, this fungus has an aecidial stage on hawthorn (Crataegus spp.)[6]. A dioecious species - both male and female forms must be grown if fruit and seed are required.

Propagation

The seed requires a period of cold stratification. The seed has a hard seedcoat and can be very slow to germinate, requiring a cold period followed by a warm period and then another cold spell, each of 2 - 3 months duration[12, 10]. Soaking the seed for 3 - 6 seconds in boiling water may speed up the germination process[9]. The seed is best sown as soon as it is ripe in a cold frame. Some might germinate in the following spring, though most will take another year. Another possibility is to harvest the seed 'green' (when the embryo has fully formed but before the seedcoat has hardened). The seedlings can be potted up into individual pots when they are large enough to handle. Grow on in pots until large enough, then plant out in early summer. When stored dry, the seed can remain viable for several years[6]. Cuttings of mature wood, 5 - 10cm with a heel, September/early autumn in a cold frame. Plant out in the following autumn[6, 12]. Layering in September/early autumn. Takes 12 months[12]. Cite as: Temperate Plants Database, Ken Fern. temperate.theferns.info. 2026-02-21. <temperate.theferns.info/plant/Juniperus+communis>

Pollinators

Wind

References

  1. [1]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.
  2. [2]A Colour Atlas of Poisonous Plants. — Frohne. D. and Pfänder. J. · Wolfe · 1984 · ISBN 0723408394 ↩︎Brilliant. Goes into technical details but in a very readable way. The best work on the subject that I've come across so far.
  3. [3]The Dictionary of Modern Herbalism. — Mills. S. Y. ↩︎An excellent small herbal.
  4. [4]IUCN Red List of Threatened Species — http://www.iucnredlist.org/ ↩︎A list of plants under threat and facing possible extinction, usually with brief details of the threats and information on habitat.
  5. [5]Planting Native Trees and Shrubs. — Beckett. G. and K. · Jarrold · 1979 · ISBN - ↩︎An excellent guide to native British trees and shrubs with lots of details about the plants.
  6. [6]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 ]).
  7. [7]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.
  8. [8]Herbs — Phillips. R. & Foy. N. · Pan Books Ltd. London. · 1990 · ISBN 0-330-30725-8 ↩︎Deals with all types of herbs including medicinal, culinary, scented and dye plants. Excellent photographs with quite good information on each plant.
  9. [9]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.
  10. [10]Conifers. — Rushforth. K. · Christopher Helm · 1987 · ISBN 0-7470-2801-X ↩︎Deals with conifers that can be grown outdoors in Britain. Good notes on cultivation and a few bits about plant uses.
  11. [11]The Garden. Volume 112. — RHS. · Royal Horticultural Society · 1987 · ISBN - ↩︎Snippets of information from the magazine of the RHS. In particular, there are articles on plants that are resistant to honey fungus, oriental vegetables, Cimicifuga spp, Passiflora species and Cucurbits.
  12. [12]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.
  13. [13]Flora of the USSR. — Komarov. V. L. · Israel Program for Scientific Translation · 1968 · http://www.biodiversitylibrary.org · ISBN - ↩︎An immense (25 or more large volumes) and not yet completed translation of the Russian flora. Full of information on plant uses and habitats but heavy going for casual readers. It can be downloaded from the Internet.
  14. [14]Trade in Indian Medicinal Plants — D.K.Ved, S.Noorunnisa Begum, & K.Ravi Kumar · Apple Academic Press; Oakville, Canada · 2018 · ISBN 978-1-77188-600-0 ↩︎
  15. [15]Sturtevant's Edible Plants of the World. — Hedrick. U. P. · Dover Publications · 1972 · ISBN 0-486-20459-6 ↩︎Lots of entries, quite a lot of information in most entries and references.
  16. [16]Food for Free. — Mabey. R. · Collins · 1974 · ISBN 0-00-219060-5 ↩︎Edible wild plants found in Britain. Fairly comprehensive, very few pictures and rather optimistic on the desirability of some of the plants.
  17. [17]Edible and Medicinal Plants. — Launert. E. · Hamlyn · 1981 · ISBN 0-600-37216-2 ↩︎Covers plants in Europe. a drawing of each plant, quite a bit of interesting information.
  18. [18]Edible Ornamental Garden. — Bryan. J. and Castle. C. · Pitman Publishing · 1976 · ISBN 0-273-00098-5 ↩︎A small book with interesting ideas for edible plants in the ornamental garden.
  19. [19]Britain's Wild Larder. — Loewenfeld. C. and Back. P. · David & Charles; Newton Abbot. · ISBN 0-7153-7971-2 ↩︎A handy pocket guide.
  20. [20]Manual of the Trees of N. America. — Sargent. C. S. · Dover Publications Inc. New York. · 1965 · http://www.biodiversitylibrary.org/ · ISBN 0-486-20278-X ↩︎Two volumes, a comprehensive listing of N. American trees though a bit out of date now. Good details on habitats, some details on plant uses. Not really for the casual reader. It can be downloaded from the internet.
  21. [21]Cornucopia - A Source Book of Edible Plants. — Facciola. S. · Kampong Publications · 1990 · ISBN 0-9628087-0-9 ↩︎Excellent. Contains a very wide range of conventional and unconventional food plants (including tropical) and where they can be obtained (mainly N. American nurseries but also research institutes and a lot of other nurseries from around the world.
  22. [22]Flora of N. America — http://flora.huh.harvard.edu/fna/ ↩︎An on-line version of the flora with an excellent description of the plant including a brief mention of plant uses.
  23. [23]Encyclopaedia of Medicinal Plants. — Chiej. R. · MacDonald · 1984 · ISBN 0-356-10541-5 ↩︎Covers plants growing in Europe. Also gives other interesting information on the plants. Good photographs.
  24. [24]Plants for Human Consumption. — Kunkel. G. · Koeltz Scientific Books · 1984 · ISBN 3874292169 ↩︎An excellent book for the dedicated. A comprehensive listing of Latin names with a brief list of edible parts.
  25. [25]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.
  26. [26]A Modern Herbal. — Grieve. · Penguin · 1984 · ISBN 0-14-046-440-9 ↩︎Not so modern (1930's?) but lots of information, mainly temperate plants.
  27. [27]The Herb Book. — Lust. J. · Bantam books · 1983 · ISBN 0-553-23827-2 ↩︎Lots of information tightly crammed into a fairly small book.
  28. [28]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.
  29. [29]Glossary of Indian Medicinal Plants (Including the Supplement). — Chopra. R. N., Nayar. S. L. and Chopra. I. C. · Council of Scientific and Industrial Research, New Delhi. · 1986 · ISBN - ↩︎Very terse details of medicinal uses of plants with a wide range of references and details of research into the plants chemistry. Not for the casual reader.
  30. [30]The Encyclopedia of Medicinal Plants — Chevallier. A. · Dorling Kindersley. London · 1996 · ISBN 9-780751-303148 ↩︎An excellent guide to over 500 of the more well known medicinal herbs from around the world.
  31. [31]A Field Guide to Medicinal Plants. Eastern and Central N. America. — Foster. S. & Duke. J. A. · Houghton Mifflin Co. · 1990 · ISBN 0395467225 ↩︎A concise book dealing with almost 500 species. A line drawing of each plant is included plus colour photographs of about 100 species. Very good as a field guide, it only gives brief details about the plants medicinal properties.
  32. [32]Aromatherapy - A guide for home use. — Westwood. C. · Amberwood Publishing Ltd · 1993 · ISBN 0-9517723-0-9 ↩︎An excellent little pocket guide. Very concise.
  33. [33]Homeopathic Materia Medica — William Boericke, M.D. · http://www.homeoint.org/books/boericmm/index.htm ↩︎An on-line version of the book
  34. [34]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.
  35. [35]CosIng — http://ec.europa.eu/growth/tools-databases/cosing/ ↩︎CosIng is the European Commission database for information on cosmetic substances and ingredients.
  36. [36]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.
  37. [37]Complete Guide to Herbs. — Holtom. J. and Hylton. W. · Rodale Press · 1979 · ISBN 0-87857-262-7 ↩︎A good herbal.
  38. [38]From Agar to Zenery. — Freethy. R. · The Crowood Press · 1985 · ISBN 0-946284-51-2 ↩︎Very readable, giving details on plant uses based on the authors own experiences.
  39. [39]Native Harvests. — Kavasch. B. · Vintage Books · 1979 · ISBN 0-394-72811-4 ↩︎Another guide to the wild foods of America.
  40. [40]A Manual of Indian Timbers. — Gamble. J. S. · Bishen Singh Mahendra Pal Singh · 1972 · ISBN - ↩︎First written in the 19th century, but still a classic, giving a lot of information on the uses and habitats of Indian trees. Not for the casual reader.
  41. [41]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.
  42. [42]The Complete Trees of N. America. Field Guide and Natural History. — Elias. T. · Van Nostrand Reinhold Co. · 1980 · ISBN 0442238622 ↩︎A very good concise guide. Gives habitats, good descriptions, maps showing distribution and a few of the uses. It also includes the many shrubs that occasionally reach tree proportions.