Black Nightshade, Solanum nigrum

Probably of South American origin, Solanum nigrum is a cosmopolitan weed that grows on cultivated, bare, waste, and disturbed ground. It is a variable, low to medium, somewhat hairy annual herb, which is very abundant in the region. Its leaves are oval to

lanceolate, usually untoothed. Flowers are white, with yellow

anthers, approximately 5 – 7 mm (1/5 – 1/3 in), in clusters of about 5. Because of their extremely small size, flowers often go unnoticed.

According to "Plants for a Future", there is a lot of disagreement over whether or not the leaves and/or fruit of this plant are poisonous. Views vary from relatively poisonous to perfectly safe to eat. The plant is cultivated as a food crop, both for its fruit and its leaves, in some parts of the world and it is probably true to say that toxicity can vary considerably according to where the plant is grown and the cultivar that is being grown.

The aforesaid source states that fruit can be eaten cooked, used in preserves, jams and pies. They have a pleasant, musky taste, somewhat like a tomato, but much less palatable. Only the fully ripe fruits should be used, inasmuch as the unripe fruits contain the toxin solanine. The fruit contains about 2.5% protein, 0.6% fat, 5.6% carbohydrate, 1.2% ash. Young leaves and new shoots can be eaten raw or cooked, as a potherb, or added to soups. This plant is cultivated as a leaf crop in some areas, but its use is inadvisable, due to possible toxicity, as stated above.

"Plants for a Future" also state that the whole plant is antiperiodic, antiphlogistic, diaphoretic, diuretic, emollient, febrifuge, narcotic, purgative and sedative. It is harvested in the autumn when both flowers and fruit are upon the plant, and is dried for later use. However, it should be used with caution, because of its possible toxicity. The leaves, stems and roots are used externally as a poultice, wash, etc., in the treatment of cancerous sores, boils, leucoderma and wounds. Extracts of the plant are analgesic, antispasmodic, anti-inflammatory and vasodilator. The plant has been used in the manufacture of locally analgesic ointments and the juice of the fruit has been used as an analgesic for toothaches.

Other, non-medical uses mentioned by "Plants for a Future", include the effective removal of PCBs from contaminated soil and the detoxification thereof. The plant is more effective in doing this if it is infected with the bacterial parasite Agrobacterium tumefaciens.

Type of plant
Annual herb

Flowering Season
January - December

Known Hazards
Berries may be toxic, especially when unripe. Sources disagree in respect of the plant's toxicity, it should, therefore, be used with caution.

Known Uses
Used in medicine as an antiperiodic, antiphlogistic, diaphoretic, diuretic, emollient, febrifuge, narcotic, purgative and sedative. Also has analgesic, antispasmodic, anti-inflammatory and vasodilator properties. The plant can be used to detoxify PCB contaminated soils. "Plants for a Future" rate this plant 2 out of 5 for edibility and 2 out of 5 for medicinal use (min. 0, max. 5).

Habitat
Cultivated, bare, waste and disturbed ground.

Distribution
Originally from South America, it has been naturilazed throughout the Mediterranean region, probably elsewhere.

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Taxonomy

Kingdom: Plantae (Plants); Subkingdom: Tracheobionta (Vascular plants); Superdivision: Spermatophyta (Seed plants); Division Magnoliophyta (Flowering plants); Class: Magnoliopsida (Dicotyledons); Subclass: Asteridae; Order: Solanales; Family: Solanaceae (Potato family); Genus: Solanum; Species: nigrum

Acknowledgments

Information on the plant's edible and medicinal uses was obtained from "Plants for a Future".