Common Australian Garden Weeds

Solanum nigrum

Scientific name: Solanum nigrum L.


Blackberry nightshade in flower.


Close-up of the flowers of blackberry nightshade, each with six white petals.


Immature and mature fruit of blackberry nightshade. Note that the fruit are not particularly glossy, are pointing downward (reflexed), and the sepals are small and not reflexed.

Common name: Blackberry nightshade

Family: Solanaceae

Origin:

Cosmopolitan weed.

Habit:

Annual or short-lived perennial herb that is usually erect and growing to 1.25 m tall.

Habitat:

Common weed of untended areas such as pastures and waste areas.

General description:

Stems and leaves
Plants are usually sparsely hairy. The leaves have stalks (petioles) 0.5-3 cm long and oval or egg-shaped leaf blades (2-13 x 1-7 cm in size) tapering to a point at the tip. The margins of the leaves are entire or slightly lobed.
Flowers and fruit
The flowers are small (8-12 mm across), white and star-shaped, with five petals and a yellow central cone. Flowers are borne in stalked clusters of 4-8 flowers. Flowering occurs from autumn to spring. The fruits are globular, shiny dull black when ripe (although sometimes remaining green) and 6-8 mm in diameter. The fruit are borne pointing downward (ie. reflexed) with small sepals that point outward.

Distinguishing features:

Herb growing to 1.25 m tall, with slightly hairy or hairless leaves that are arranged alternately on the stem. Flowers are small, white and star-like and borne on individual stalks. Fruits are dull green, usually turning black as they mature, and are 6-8 mm in diameter. Very similar to Solanum americanum (blackberry nightshade). However, this species has glossy fruit that are borne almost pointing upward, with larger downward pointing sepals.

Noxious status:

Not noxious.

Sources:

Stanley, T.E. and Ross, E.M. (1983-1989). Flora of South-eastern Queensland. Volume 2. Department of Primary Industries, Brisbane.

Wilson, B.J., Hawton, D. and Duff, A.A. (1995). Crop Weeds of northern Australia: identification at seedling and mature stages. Queensland Department of Primary Industries, Brisbane.