Citrus sinensis
Rutaceae FAMILY

Citrus sinensis

Citrus sinensis

Edibility
4/5
Medicinal
3/5

Safety & Hazards

None known

Cultivation Details

HabitEvergreen Tree
Growth—

Prefers a moderately heavy loam with a generous amount of compost and sand added and a very sunny position[1, 2]. Prefers a pH between 5 and 6[2]. Tolerates a pH in the range 4.3 to 8.3. Plants are intolerant of water logging[3]. When growing plants in pots, a compost comprising equal quantities of loam and leafmould plus a little charcoal should produce good results[4]. Do not use manure since Citrus species dislike it[4]. When watering pot plants it is important to neither overwater or underwater since the plant will soon complain by turning yellow and dying. Water only when the compost is almost dry, but do not allow it to become completely dry[4]. The sweet orange is widely grown for its edible fruit in warm temperate and tropical zones, there are many named varieties[5]. In Britain it can be grown in a pot placed outdoors in the summer and brought into a greenhouse during the winter[3]. Plants are almost hardy in the mildest areas of Britain[1] but the fruit is insipid if it is developed when the mean temperature is below 18°c[3]. The young growth in spring, even on mature plants, is frost-tender and so it is best to grow the plants in a position sheltered from the early morning sun[PFAF]. The flowers are sweetly scented[6]. Plants dislike root disturbance and so should be placed into their permanent positions when young. If growing them in pots, great care must be exercised when potting them on into larger containers[7].

Propagation

The seed is best sown in a greenhouse as soon as it ripe after thoroughly rinsing it[8, 2]. Sow stored seed in early spring in a greenhouse[3]. Germination usually takes place within 2 - 3 weeks at 13°c. Seedlings are liable to damp off so they must be watered with care and kept well ventilated. The seed is usually polyembrionic, two or more seedlings arise from each seed and they are genetically identical to the parent but they do not usually carry any virus that might be present in the parent plant[2]. When large enough to handle, prick the seedlings out into individual pots and grow them on in the greenhouse for at least three growing seasons before trying them outdoors. Plant them out in the summer and give them some protection from the cold for their first few winters outdoors. Cuttings of half-ripe wood, mid summer in a frame. Layering in early autumn. Cite as: Temperate Plants Database, Ken Fern. temperate.theferns.info. 2026-02-20. <temperate.theferns.info/plant/Citrus+sinensis>

Pollinators

Apomictic, Insects

References

  1. [1]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 ]).
  2. [2]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.
  3. [3]Growing Unusual Fruit. — Simmons. A. E. · David & Charles; Newton Abbot. · 1972 · ISBN 0-7153-5531-7 ↩︎A very readable book with information on about 100 species that can be grown in Britain (some in greenhouses) and details on how to grow and use them.
  4. [4]Conservatory and Indoor Plants Volumes 1 & 2 — Phillips. R. & Rix. M. · Pan Books, London. · 1998 · ISBN 0-330-37376-5 ↩︎Excellent photos of over 1,100 species and cultivars with habits and cultivation details plus a few plant uses. Many species are too tender for outdoors in Britain though there are many that can be grown outside.
  5. [5]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.
  6. [6]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.
  7. [7]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.
  8. [8]Growing from Seed. Volume 4. — Bird. R. (Editor) · Thompson and Morgan. · 1990 · ISBN - ↩︎Very readable magazine with lots of information on propagation. A good article on Yuccas, one on Sagebrush (Artemesia spp) and another on Chaerophyllum bulbosum.
  9. [9]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.
  10. [10]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.
  11. [11]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.
  12. [12]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.
  13. [PFAF]Plants for a Future — pfaf.org ↩︎