Black Nightshade
Solanum ptycanthum
Nightshade family (Solanaceae)

Description: This rather variable annual plant is native or adventive. It is about 1-3' tall and branches frequently. The stems are more or less hairy, but not prickly. The alternate leaves are up to 3" long and 2" across, with margins that are smooth, undulate, or bluntly dentate. They are usually broadly lanceolate, ovate, or deltoid, with a fine pubescence or scattered short hairs across the surface, especially on the undersides. The petioles are long and slender. The foliage of Black Nightshade is green or dark green. From the upper portion of the stems (rather than the leaf axils), there occasionally develops nodding umbels of white flowers from a short stalk (peduncle) about 1" long. Each umbel has 3-10 flowers. Both the peduncle of the umbel and the pedicels of the flowers are green and finely pubescent. Each flower is about 1/3" across, and consists of a star-like white corolla with 5 tapering lobes that curve backward. Projecting from the center of the corolla, there are 5 stamens with large yellow anthers that are appressed together against the pistil. The green sepals are shaped like blunt triangles. 

The blooming period usually occurs during the summer or early fall. A single plant may produce flowers sporadically for about 2 months. Each flower is replaced by a small round berry about 1/3" across. A berry has a smooth surface that is initially green, but later becomes black as it matures. This berry is juicy and contains several flat seeds that are yellow or brown. The root system consists of a slender taproot that branches frequently. This plant spreads by reseeding itself.

Cultivation: Black Nightshade is an adaptable plant that flourishes in full or partial sun, moist to mesic situations, and almost any kind of soil, especially fertile loam. The size of a plant depends heavily on moisture levels and soil fertility. The foliage is usually little bothered by insect pests and disease.

Range & Habitat: This common plant has been observed in most counties of Illinois (see Distribution Map). It can be found in thickets, openings in degraded woodlands, rocky bluffs, cropland and pastures, gardens, vacant lots, areas along railroads, and waste areas. This plant is more common at sites with a history of disturbance and is rather weedy. Different authorities provide differing accounts of the origination of Black Nightshade: Some claim it is a native species with a worldwide distribution, while others believe that it is adventive from Europe, South America, or India.

Faunal Associations: Bumblebees collect pollen from the flowers. The caterpillars of the moth Heliothis subflexus (Subflexus Straw) feed on this plant, as well as other members of the Nightshade family. The small black berries are eaten primarily by birds, which includes the following: Wood Duck, Sora Rail, Ring-Necked Pheasant, Wild Turkey, Cardinal, Catbird, Eastern Meadowlark, and Swamp Sparrow. These birds help to distribute the seeds far and wide. Mammalian herbivores avoid this plant because the foliage contains the toxic alkaloid, solanum.

Photographic Location: On the grounds of the webmaster's apartment complex in Urbana, Illinois.

Comments: The berries of Black Nightshade are edible to humans, if they are fully ripe and eaten in small quantities. Green berries contain the toxic alkaloid, solanum, like the foliage. There are several Solanum spp. that occur in Illinois. They fall into two groups: Those species with sharp bristles or spines, and those species without sharp bristles or spines. Black Nightshade falls into the latter group. The Solanum spp. in this latter group can be distinguished from each other by the appearance of their leaves: Black Nightshade has broader leaves that are without deep lobes along their sides, and they lack conspicuous silvery hairs. Some Solanum spp. have mature berries that are either green or yellow, but the mature berries of Black Nightshade are always black. Other scientific names for this species are Solanum nigrum and Solanum americanum.