Black Nightshade is a native erect annual, growing from 6 to 24 inches high, with round, slender, hollow, branching stems that are slightly hairy and sometimes show purple at the joints.
The leaves are alternate, a dull green to dark green, long ovate, with pointed tips and long slender grooved stalks. The first leaves are smooth, somewhat egg-shaped. The later leaves take on a more diamond shape with margins either entire or irregularly toothed, sometimes resembling lobes. Older leaves are often bitten full of small holes by a small flea beetle.
The inflorescence is a tight umbel like cluster of 3 to 10 5-parted flowers, the clusters on drooping stalks below the leaf axils (that is - from the side of the stem), not opposite the leaf axils as in Climbing Nightshade. Both the flower stalks and the stalk of the cluster have fine hair. These clusters usually droop.
Flowers are 1/4 to 1/3 inch wide and each on a 1 inch stalk, The corolla is white to purple tinged, wheel or star shaped with lobes that reflex backward at maturity but not to the extent of Climbing Nightshade. There are 5 stamens with large yellow anthers that unite in a cone around the style which is greenish with a blunt stigma. The lobes of the calyx are green, much shorter than the corolla lobes, triangular shaped and spreading and persistent on the base of the fruit.
Seed: The mature flowers produce a round smooth berry, 1/4 inch in diameter, that is green, turning black at maturity, which contains up to 12 small whitish, angled, but flattened, seeds, each about 2 mm long.
Toxic: See text below the photos.
Habitat: Black Nightshade grows in various soils of disturbed sites that have moisture and in riparian areas. It does well in partial shade. It reproduces from re-seeding.
Names: The genus name Solanum comes from the Latin Solor, meaning "I ease" referring to the somewhat narcotic power of some folk medicines created from the plant. The species name, nigrum means 'black'. The author name for the plant classification - 'L.' is for Carl Linnaeus (1707-1778), Swedish botanist and the developer of the binomial nomenclature of modern taxonomy. There are a number of varieties of S. nigrum, most of which are now considered as synonyms for other species of Solanum. The old common name of 'Petty Morel' was used by old herbalists in the old world to distinguish the berries of this plant from those of Deadly Nightshade (Belladonna), which was referred to as the 'Great Morel'. 'American Black Nightshade' is used to separate the species from a close relative - West Indian Black Nightshade, S. ptycanthemum Dunal. They are so close in fact, that some authorities no longer try to separate them - see notes below the photos. As to the author for S. ptycanthemum - ‘Dunal’ refers to Michel Félix Dunal (1789 - 1856), French botanist, chair of the Dept. of Natural History at the University of Montpellier. His main research and writing was on the Nightshades in the genus Solanum.
Comparisons: Most frequently seen is the Bittersweet or Climbing Nightshade, Solanum dulcamara L., where the berries turn red at maturity, the plant vines, the corolla is purple and it is perennial. S. dulcamara is an introduced naturalized plant. See the notes below on Minnesota species names.
Above: Black Nightshade flowers have a corolla that is white to purple tinged, wheel or star shaped with lobes that reflex backward at maturity. There are 5 stamens with large yellow anthers that unite in a cone around the style.
Below: 1st photo - The flower with petals reflexed. The style is greenish with a blunt stigma. 2nd photo - An example of the upright multiple branching of Black Nightshade.
Below: 1st photo - The lobes of the calyx are very short, triangular shaped and slightly spreading. Note that the cluster rises between leaf axils not opposite of leaf axil. 2nd photo - Fruit is green at first before turning black. The calyx lobes are persistent on the the fruit.
Below: Mature black fruit. Each berry contains up to 12 small angled but flattened seeds.
Below: The leaves are alternate, a dull green to dark green, long ovate, with pointed tips and long slender grooved stalks. The first leaves are smooth, somewhat egg-shaped. The later leaves take on a more diamond shape with margins either entire or irregularly toothed, sometimes resembling lobes. Older leaves are often bitten full of small holes by a small flea beetle. The inflorescence is a tight umbel like cluster of 3 to 10 flowers.
Notes: Black Nightshade is not indigenous to the Garden but it was present by the time of Martha Crone's 1951 Garden census. The The University of Minnesota herbarium reports there are 7 species of Solanum in Minnesota but the DNR only lists 5 on their county survey data. (2019) Two other species of the Nightshade Family are found in the Garden - Climbing Nightshade and Clammy Groundcherry. In North America, S. nigrum is found across the continent except the west coast states and provinces and the far north provinces of Canada.
Confusing name issues: The MN-DNR lists S. nigrum L. var. virginicum as the native Minnesota species, names it Black Nightshade, and lists it as present in most counties of the state. The differences with West Indian Black Nightshade, S. ptycanthemum, and American Black Nightshade, S. nigrum, are slight and the many varieties in the scientific classification are confusing. The University of Minnesota Herbarium now states that the differences between the two species are uncertain and now seems to prefer classifying the plants that have been collected in the state as - West Indian Black Nightshade, S. ptycanthemum
Toxic: The poisonous qualities of the plant vary with the period of growth. The leaves and green berries, containing the narcotic alkaloid Solanine, are poisonous to humans and mammals. After the berries mature and turn black, they are edible, in limited quantities, by adult humans but should be avoided by children. The level of solanine in the plant varies with the season, more early, less later. All members of the Nightshade family have a narcotic property, which is why some of them are highly poisonous. However, this plant family also includes the tomato and the potato. Black Nightshade is said to possess greater narcotic properties than the Climbing Nightshade. (Ref. #7). The plant must not be confused with Belladonna, or Deadly Nightshade (Atropa bella-donna L.), which however, is quite restricted in distribution in the United States - and not known in Minnesota. Culpepper (Ref. #4b) wrote: "Do not mistake the deadly nightshade for this, if you know it not, you may then let them both alone."
Fernald (Ref.#6) writes that Black Nightshade was sometime cultivated under the name "Garden Huckleberry" with the ripe berries being used as cooked fruit for pies and preserves, but they tasted not like Huckleberries but like a mildly bitter tomato. Apparently it was common in the farm country of the central U.S. for the ripe berries to be cooked and used that way without ill effects. He references a report of Professor Charles Bessey from 1905 that appeared in the American Botanist about where this use was common. [Eloise Butler said that Bessey was "the most enthusiastic teacher I ever met". He was a professor at the University of Iowa and later at Nebraska. Eloise took many summer botany excursions with him prior to becoming curator of the Garden.]
References: Plant characteristics are generally from sources 1A, 32, W2, W3, W7 & W8 plus others as specifically applied. Distribution principally from W1, W2 and 28C. Planting history generally from 1, 4 & 4a. Other sources by specific reference. See Reference List for details.
Identification booklet for most of the flowering forbs and small flowering shrubs of the Eloise Butler Wildflower Garden. Details Here.
Friends of the Wild Flower Garden, Inc. Text and photos are by G. D. Bebeau unless otherwise credited. "www.friendsofthewildflowergarden.org"