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Rosaceae FAMILY

Prunus dulcis

Prunus dulcis

Edibility
5/5
Medicinal
3/5

Safety & Hazards

The plant (especially the seed and young shoots) contains cyanogenic glycosides, especially amygdalin and prunasin. 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 fruits and flowers of most members of this genus generally have low or very low concentrations of this toxin, though the seeds and young shoots can contain much higher levels. The levels of toxin can be detected by the level of bitterness:- for example sweet tasting almond seeds are a major food crop and are often eaten in quantity, whilst bitter tasting almond seeds are used as a flavouring (in marzipan for example) but are not usually eaten on their own. In general, it can be considered safe to eat any fruit or seed from species in this genus that either have a sweet flavour or are slightly bitter. Great caution should be taken, however, if the flavour is moderately to very bitter[PFAF].

Cultivation Details

HabitDeciduous Tree
Growth—

The almond prefers a Mediterranean or a Continental climate, with a clear distinction between winter and spring, in milder maritime areas it can be induced into flower too early in the season and is then very liable to be damaged by frosts[3]. Thrives in a well-drained moisture-retentive loamy soil[4, 3]. Prefers some lime in the soil but is likely to become chlorotic if too much lime is present[5]. Succeeds in sun or partial shade though it fruits better in a sunny position[4, 3]. The almond is often cultivated in the temperate zone for its edible seeds, there are many named varieties[6, 3]. The United States now dominates world almond production with over 40% of the annual crop, all of it grown in or near the Central Valley of California. The in-shell 'nuts' sold in stores are the pits of drupes with the leathery mesocarp removed[7]. There are two basic forms of almonds, one with bitter seeds and one with 'sweet' seeds. The bitterness is caused by the presence of cyanogenic glycosides (see notes above). Although the bitter forms are used in making marzipan and as a food flavouring, the seeds themselves should not be eaten in anything other than small quantities. Even the sweet forms should not be eaten in very large quantities. (Approximately 900 of the sweet seeds at one time is considered to be a toxic dose for the average adult). Trees are hardier when grown on a plum rootstock[4]. Almond seedlings are the preferred rootstock when plants are grown on hot dry soils, peach rootstocks are better for heavier soils[3]. Almond is among the earliest blossoming trees and one of the first signs of spring in areas where it is grown[7]. There is likely to be a shortage of pollinating insects around when the tree is in flower so hand pollination may improve the crop. Although partially self-fertile, better crops are obtained if at least 2 different cultivars are grown[3]. Most members of this genus are shallow-rooted and will produce suckers if the roots are damaged[1]. Plants in this genus are notably susceptible to honey fungus[3].

Propagation

Seed - requires 2 - 3 months cold stratification and is best sown in a cold frame as soon as it is ripe[3]. Sow stored seed in a cold frame as early in the year as possible[3]. Protect the seed from mice etc. The seed can be rather slow, sometimes taking 18 months to germinate[8]. Prick out the seedlings into individual pots when they are large enough to handle. Grow them on in a greenhouse or cold frame for their first winter and plant them out in late spring or early summer of the following year. Cuttings of half-ripe wood with a heel, mid summer in a frame[4, 3]. Difficult. Softwood cuttings from strongly growing plants in spring to early summer in a frame[3]. Cuttings of mature wood, late autumn in a frame. Layering in spring. Cite as: Temperate Plants Database, Ken Fern. temperate.theferns.info. 2026-02-21. <temperate.theferns.info/plant/Prunus+dulcis>

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]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.
  4. [4]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.
  5. [5]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 ]).
  6. [6]Nuts. — Howes. F. N. · Faber · 1948 · ISBN - ↩︎Rather old but still a masterpiece. Has sections on tropical and temperate plants with edible nuts plus a section on nut plants in Britain. Very readable.
  7. [7]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.
  8. [8]The Reference Manual of Woody Plant Propagation. — Dirr. M. A. and Heuser. M. W. · Athens Ga. Varsity Press · 1987 · ISBN 0942375009 ↩︎A very detailed book on propagating trees. Not for the casual reader.
  9. [9]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.
  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. [11]Flowers of the Mediterranean. — Polunin. O. and Huxley. A. · Hogarth Press · 1987 · ISBN 0-7012-0784-1 ↩︎A very readable pocket flora that is well illustrated. Gives some information on plant uses.
  12. [12]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.
  13. [13]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.
  14. [14]A Modern Herbal. — Grieve. · Penguin · 1984 · ISBN 0-14-046-440-9 ↩︎Not so modern (1930's?) but lots of information, mainly temperate plants.
  15. [15]Mansfeld's Database of Agricultural and Horticultural Plants — http://mansfeld.ipk-gatersleben.de/pls/htmldb_pgrc/f?p=185:3:4292127278597336 ↩︎Terse details of a huge range of useful plants.
  16. [16]Plants for Man. — Schery. R. W. ↩︎Fairly readable but not very comprehensive. Deals with plants from around the world.
  17. [17]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.
  18. [18]Vegetable Gums and Resins. — Howes. F. N. · Faber · ISBN 81-88818-17-8 ↩︎A very good book dealing with the subject in a readable way.
  19. [19]The Herb Book. — Lust. J. · Bantam books · 1983 · ISBN 0-553-23827-2 ↩︎Lots of information tightly crammed into a fairly small book.
  20. [20]Medicinal Plants of China — Duke. J. A. and Ayensu. E. S. · Reference Publications, Inc. · 1985 · ISBN 0-917256-20-4 ↩︎Details of over 1,200 medicinal plants of China and brief details of their uses. Often includes an analysis, or at least a list of constituents. Heavy going if you are not into the subject.
  21. [21]Nature's Colors - Dyes from Plants. — Grae. I. · MacMillan Publishing Co. New York. · 1974 · ISBN 0-02-544950-8 ↩︎A very good and readable book on dyeing.
  22. [22]Herbs of Greece. — Niebuhr. A. D. · Herb Society of America. · 1970 · ISBN - ↩︎A pleasant little book about Greek herbs.
  23. [23]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.
  24. [PFAF]Plants for a Future — pfaf.org ↩︎