Common Name: Sow Thistle

General Information

Sonchus oleraceus is an annual to biennial plant that can grow up to 140cm tall. The stem can be simple or branched[].
This plant is harvested from the wild for local use as a food and medicine. It is sometimes traded in local markets. It has been cultivated on a small scale for its edible leaves in several countries[, ].
Sonchus oleraceus is a common garden weed producing many small light seeds that disperse readily by wind and water, often for long distances. It has spread from temperate Europe to become a weed in most parts of the world.

Known Hazards

The white latex in the plant is suspected of being mildly poisonous, and rare cases of poisoning of lambs (in Somalia) and horses (in Australia) have been attributed to it[].

Botanical References

Range

Europe, including Britain, south and east from Scandanavia to N. Africa, N. and W. Asia. A cosmopolitan weed.

Habitat

Waysides, waste and cultivated ground[]. A common weed, avoiding acid soils and shady positions[]. Mainly found in disturbed localities, including farmland, abandoned fields and recently burned fields, at elevations up to 2,650 metres[].

Properties

Weed Potential	Yes
Edibility Rating
Medicinal Rating
Habit	Annual/Biennial
Height	1.00 m
Pollinators	Bees, Flies
Cultivation Status	Wild

Cultivation Details

Succeeds in most soils in a sunny position.

Edible Uses

Young leaves - raw or cooked[, , , , ]. This species has the nicest tasting leaves of the genus[], they usually have a mild agreeable flavour[] especially when young, though turn bitter as they age[, ]. They can be added to salads, cooked like spinach or used in soups etc[]. The leaves contain about 30 - 40mg of vitamin C per 100g[], 1.2% protein, 0.3% fat, 2.4% carbohydrate, 1.2% ash[]. A zero moisture analysis is also available[]. It might be best, though it is not essential, to remove the marginal prickles[].

Stems - cooked like asparagus or rhubarb[]. They are best if the outer skin is removed first[].

Young root - cooked[]. Young roots are juicy[]. They are woody and not very acceptable[].

The milky sap has been used as a chewing gum by the Maoris of New Zealand[].

Medicinal

The plant is emmenagogue and hepatic[, ]. An infusion has been used to bring on a tardy menstruation and to treat diarrhoea[].

The latex in the sap is used in the treatment of opium addiction, warts and cancer[, ].
The gum has been used as a cure for the opium habit[].

The stem juice is a powerful hydrogogue and cathartic, it should be used with great caution since it can cause colic and tenesmus[].

The leaves are said to clear infections, and are diuretic, hepatic, sedative and stomachic[]. They are also used in the treatment of eye problems, gastritis, salmonella infection, kwashiorkor and anaemia[].
The leaves are applied as a poultice to inflammatory swellings[].
The use of leaf sap to treat earache and deafness is probably effective in cases where excessive amounts of earwax are the underlying cause of the problem[].

An infusion of the leaves and roots is febrifuge and tonic[].

The roots are abortifacient, purgative and vermifuge[].

Callus cultures of the plant have shown broad spectrum antibacterial activity[].
The aqueous extract demonstrated acaricidal activity against the two-spotted spider mite, Tetranychus urticae[].

Agroforestry Uses:

The plant is a good companion for onions, tomatoes, corn as well as the cucumber and squash family[].

Other Uses

The latex in the stem contains 0.14% rubber, but this is much too low for commercial exploitation[].

Propagation

Seed - sow spring in situ. This species is a common garden weed and should not need any encouragement.