Lactuca sativa crispa

Taxonomy and growth

Family

Compositae

Genus

Lactuca

Life cycle

annual, biennial

Height

0.9 m

Spread

0.25 m

Fertility

Self fertile, Flies, Self

Flower type

hermaphrodite

Pollinators

Flies, Self

Uses

Edible uses

This section contains historical Plants For A Future notes marked noncommercial.

Leaves - raw or cooked^[24][23]. A mild slightly sweet flavour with a crisp texture, lettuce is a very commonly used salad leaf and can also be cooked as a potherb or be added to soups etc^[22]. This variety forms a loose rosette of leaves and can be harvested on a cut and come again basis. Seed - sprouted and used in salads or sandwiches^[22]. An edible oil is obtained from the seed^[24]. The seed is very small, extraction of the oil on any scale would not be very feasible[K]. There are no edible uses listed for Lactuca sativa crispa.

Medicinal uses

Historical medicinal uses. These records describe reported uses. They do not establish safety or effectiveness. Ask a qualified health professional before using any plant medicinally.

This section contains historical Plants For A Future notes marked noncommercial.

The whole plant is rich in a milky sap that flows freely from any wounds. This hardens and dries when in contact with the air^[18]. The sap contains 'lactucarium', which is used in medicine for its anodyne, antispasmodic, digestive, diuretic, hypnotic, narcotic and sedative properties^{[21][12][19][4][8][13][16]}. Lactucarium has the effects of a feeble opium, but without its tendency to cause digestive upsets^[18], nor is it addictive^[20]. It is taken internally in the treatment of insomnia, anxiety, neuroses, hyperactivity in children, dry coughs, whooping cough, rheumatic pain etc^[16]. Concentrations of lactucarium are low in young plants and most concentrated when the plant comes into flower^[16]. It is collected commercially by cutting the heads of the plants and scraping the juice into china vessels several times a day until the plant is exhausted^[18]. The cultivated lettuce does not contain as much lactucarium as the wild species, most being produced when the plant is in flower^[18]. An infusion of the fresh or dried flowering plant can also be used^[21]. The plant should be used with caution, and never without the supervision of a skilled practitioner. Even normal doses can cause drowsiness whilst excess causes restlessness^[16] and overdoses can cause death through cardiac paralysis^[20][21]. Some physicians believe that any effects of this medicine are caused by the mind of the patient rather than by the medicine^[13]. The sap has also been applied externally in the treatment of warts^[15]. The seed is anodyne and galactogogue^[14]. Lettuce has acquired a folk reputation as an anaphrodisiac, anodyne, carminative, diuretic, emollient, febrifuge, hypoglycaemic, hypnotic, narcotic, parasiticide and sedative^[14].

Material uses

This section contains historical Plants For A Future notes marked noncommercial.

Parasiticide^[5]. No further details are given, but it is probably the sap of flowering plants that is used. The seed is said to be used to make hair grow on scar tissue^[14].

Environment

Range

Of garden origin, probably derived from L. serriola.

Habitat

Not known in the wild.

Light

full sun

Shade tolerance

light shade

Water

moderate

Hardiness

Zone 6+

Soil textures

sandy, loamy

Soil pH

neutral, alkaline

Drainage

well drained

Tolerates Nutritionally Poor Soil

No

Drought

intolerant

Propagation

This section contains historical Plants For A Future notes marked noncommercial.

Cultivation

This section contains historical Plants For A Future notes marked noncommercial.

Prefers a light sandy loam^[1]. Succeeds in most well-drained, humus-rich soils but dislikes acid conditions^[1][3]. Plants strongly dislike dry conditions, quickly running to seed in such a situation. Early and late sowings are best in a sunny position, but summer crops are best given a position with some shade in order to slow down the plants tendency to go to seed and to prevent the leaves becoming bitter^[6][9]. The garden lettuce is widely cultivated in many parts of the world for its edible leaves and is probably the most commonly grown salad plant. This is the curled or leaf lettuce. It does not form a central heart but produces a loose rosette of basal leaves and can be harvested on a cut and come again basis. There are many named varieties^[7] capable of providing fresh leaves throughout the year if winter protection is given in temperate areas. Lettuces are quite a problematic crop to grow. They require quite a lot of attention to protect them from pests such as slugs, aphids and birds. If the weather is hot and dry the plants tend to run very quickly to seed, developing a bitter flavour as they do so. In wet weather they are likely to develop fungal diseases. In addition, the seed needs to be sown at regular intervals of 2- 3 weeks during the growing season in order to provide a regular supply of leaves. Lettuces make a good companion plant for strawberries, carrots, radishes and onions^[6][9][11]. They also grow well with cucumbers, cabbages and beetroot^[11].

Related plants

• Lactuca biennisTall Blue Lettuce
• Lactuca canadensisCanada Lettuce
• Lactuca capensis
• Lactuca debilis

References

1. F. Chittendon. RHS Dictionary of Plants plus Supplement. 1956 Oxford University Press 1951-00-00

   ↩1↩2

2. Triska. Dr. Hamlyn Encyclopaedia of Plants. Hamlyn 1975-00-00 ISBN 0-600-33545-3

   ↩

3. Simons. New Vegetable Growers Handbook. Penguin 1977-00-00 ISBN 0-14-046-050-0

   ↩

4. Mills. S. Y. The Dictionary of Modern Herbalism.

   ↩

5. Stuart. Rev. G. A. Chinese Materia Medica. Taipei. Southern Materials Centre

   ↩

6. Philbrick H. and Gregg R. B. Companion Plants. Watkins 1979-00-00

   ↩1↩2

7. Facciola. S. Cornucopia - A Source Book of Edible Plants. Kampong Publications 1990-00-00 ISBN 0-9628087-0-9

   ↩

8. Emboden. W. Narcotic Plants Studio Vista 1979-00-00 ISBN 0-289-70864-8

   ↩

9. Riotte. L. Companion Planting for Successful Gardening. Garden Way, Vermont, USA. 1978-00-00 ISBN 0-88266-064-0

   ↩1↩2

10. Huxley. A. The New RHS Dictionary of Gardening. 1992. MacMillan Press 1992-00-00 ISBN 0-333-47494-5

11. Allardice.P. A - Z of Companion Planting. Cassell Publishers Ltd. 1993-00-00 ISBN 0-304-34324-2

    ↩1↩2

12. Lust. J. The Herb Book. Bantam books 1983-00-00 ISBN 0-553-23827-2

    ↩

13. Weiner. M. A. Earth Medicine, Earth Food. Ballantine Books 1980-00-00 ISBN 0-449-90589-6

    ↩1↩2

14. Duke. J. A. and Ayensu. E. S. Medicinal Plants of China Reference Publications, Inc. 1985-00-00 ISBN 0-917256-20-4

    ↩1↩2↩3

15. Foster. S. & Duke. J. A. A Field Guide to Medicinal Plants. Eastern and Central N. America. Houghton Mifflin Co. 1990-00-00 ISBN 0395467225

    ↩

16. Bown. D. Encyclopaedia of Herbs and their Uses. Dorling Kindersley, London. 1995-00-00 ISBN 0-7513-020-31

    ↩1↩2↩3↩4

17. Thompson. B. The Gardener's Assistant. Blackie and Son. 1878-00-00

18. Grieve. A Modern Herbal. Penguin 1984-00-00 ISBN 0-14-046-440-9

    ↩1↩2↩3↩4

19. Uphof. J. C. Th. Dictionary of Economic Plants. Weinheim 1959-00-00

    ↩

20. Chiej. R. Encyclopaedia of Medicinal Plants. MacDonald 1984-00-00 ISBN 0-356-10541-5

    ↩1↩2

21. Launert. E. Edible and Medicinal Plants. Hamlyn 1981-00-00 ISBN 0-600-37216-2

    ↩1↩2↩3

22. Facciola. S. Cornucopia - A Source Book of Edible Plants. Kampong Publications ISBN 0-9628087-0-9 (1990-00-00)

    • ISBN 0-9628087-0-9
    ↩1↩2

23. Thompson. B. The Gardener's Assistant. Blackie and Son. (1878-00-00)

    ↩

24. Chiej. R. Encyclopaedia of Medicinal Plants. MacDonald ISBN 0-356-10541-5 (1984-00-00)

    • ISBN 0-356-10541-5
    ↩1↩2