Nightshades Solanaceae family


Nightshades encompass a very large family, a large very dysfunctional family!  Many of these family members are good citizens of the plant world, mostly, but a few of them are downright anti-social.  The good guys help to feed the world, beautify the space around them and help relieve some of the physical pain of their human neighbors.  Let’s start with the good guys.


Nightshades are members of the Solanaceae family and are an economically important family of flowering plants.  The family ranges from annual and perennial herbs to vines, lianas, epiphytes, shrubs and trees and includes a number of important agricultural crops, medicinal plants, spices, weeds and ornamentals.  The Solanaceae consists of 98 genera and some 2700 species.  The family has a worldwide distribution, being present on all continents except Antarctica.  The greatest diversity in species is found in South and Central America.

The most economically important genus of the family is Solanum, which includes the potato, the tomato, and the eggplant or aubergine.  Another important genus is Capsicum which produces both chili peppers and sweet peppers.  The genus Physios produces the ground cherries as well as the tomatillo the Cape gooseberry and the Chinese lantern.  Nicotiana contains among other species, tobacco.  Some other important members of the Solanaceae include ornamentals such as Petunia,  Browalia, Datura,  Brugmansia.,  Mandragora (Mandrake) and the queen of poisons, Atropa belladonna or deadly nightshade.  Many of the Solanaceae, such as Petunia and tobacco are used as model organisms in the investigation of fundamental biological questions at the cellular, molecular and genetic levels.

So let’s look at this family Solanaceae, first the potato, my personal favorite.  In my mind potatoes are the staff of life and if the book, The Martian, is anywhere near correct I am not far off!

Potatoes are herbaceous annuals that grow about 24” tall; they bear white, pink, red or blue flowers.  In general the tubers of varieties with white flowers have white skins while those varieties with colored flowers tend to have pinkish skin.  Tubers form in response to the decreasing day length.  After flowering the plants produce small green fruits that resemble green cherry tomatoes each containing about 300 seeds.  Like all parts of the plant except the tubers they contain the toxic alkaloid selinene and are therefore unsuitable for consumption.  All new potatoes are grown from seeds called, “true potato seed” to distinguish from seed tubers.

The tomato is native to South and Central America.  Native versions are small, like cherry tomatoes and most likely yellow.  Because the tomato is a member of the nightshade family it was thought to be poisonous but is not, however the leaves are poisonous, not deadly but poisonous to animals that have eaten them growing in the garden.  The fruit itself contains low levels of tomatine but are not dangerous for consumption.  There are approximately 7500 tomato varieties.

Like most nightshades the eggplant fruit is edible but the leaves and flowers are poisonous if eaten in large quantities.  Botanically the eggplant is classified as a berry, the fruit contains numerous small soft seeds, and though edible they taste bitter because they contain nicotinoid alkaloids.  There is a pattern here, let’s move on to the not so friendly family members and start with the ones that are helpful/pretty/dangerous.

Nicotiana is indigenous to the Americas, Australia, southwest Africa and the South Pacific.  While there are more than 70 species of tobacco the chief commercial crop is N. tabacum and the potent species N. rustica.  Smoked or chewed tobacco is a risk factor for many diseases, heart, liver, lungs and several different cancers. Tobacco contains the alkaloid nicotine, a stimulant. The WHO has named tobacco as the world’s single greatest cause of preventable death. 

Datura Stramonium’s common names are Jimson Weed, Devil’s snare, thorn apple, moon flower and locoweed.  Datura probably originated in Mexico but has naturalized in many other regions.  The plant is a foul smelling, erect, annual, freely branching herb that forms a bush up to five feet tall with erect flowers.  Datura has been used in traditional medicine to relieve asthma symptoms and as an analgesic during surgery and bone setting.  It is also a powerful hallucinogen and deliriant which is used spiritually for the intense visions it produces.  The tropane alkaloids responsible for the medicinal and hallucinogenic properties are fatally toxic in only slightly higher doses used for these purposes.  The amount of toxins varies widely from plant to plant.  As much as 5.1 variation can be found from plant to plant and a given plants toxicity depends on its age, where it is growing and local weather conditions.   Additionally within a given Datura plant toxin concentration varies by part and even leaf to leaf.  Spiritual uses:  the ancient inhabitants of what is today central and southern California ingested the small black seeds to “commune” with deities through visions.  Across the Americas the plant was used by Algonquin, Cherokee and Luiseño tribes in sacred ceremonies.  In Haiti it was used as a central ingredient of the concoction voodoo priests used to create zombies.

The common name Datura has its roots in ancient India, where the plant is considered sacred, believed to be a favorite of the Hindu god Shiva Nataraja.

The hallucinations brought on by the use of this plant are said not to be frightening but spiritual and funny and when it wears off the person has no memory of the time under the influence.  When Jamestown was settled, some British soldiers consumed the plant in a boiled salad; they spent 11 days in altered mental states.  An account in “The History and Present State of Virginia, 1795” stated that the victims were “In a frantic condition they were confined, lest they should, in their folly, destroy themselves-though it was observed that all their actions were full of innocence and good nature.  Indeed, they were not very cleanly; for they would have wallowed in their own excrements, if they had not been prevented.  A thousand such simple tricks they played, and after eleven days returned themselves again, not remembering anything that passed.”   The name Jimson Weed is a corruption of the name Jamestown.

Brugmansia is a closely related relative of Datura.  It is a larger plant with pendulous fragrant flowers and without the spiked seed pods of Datura.  Native to South America it has naturalized into North America.  Today Brugmansia is most often grown as a flowering ornamental.  In modern medicine the alkaloids found in the plant, scopolamine, hyosyamine and atropine have proven to be of value, however, many of these alkaloids or their equivalent are now artificially synthesized. 

Several South American cultures have used Brugmansia as a treatment for unruly children, that they might be admonished directly by their ancestors in the spirit world and thereby become more compliant.  In ancient times the plant was mixed with maize beer and tobacco leaves and used to drug wives and slaves so they could be buried alive with their dead lords.  Like Datura all parts of this plant is poisonous and unpredictable, in 1994, 112 teenagers were admitted to hospitals from ingesting Brugmansia in Florida alone

And now to the queen of poisons deadly nightshade; Atropa belladonna, named for the Greek goddess Atropas, one of the three Greek Fates, who would determine the course of a man’s life by the weaving of threads that symbolized his birth, the events in his life, and finally his death, with Atropos cutting these threads to mark the last of these.  The name Atropa belladonna is attributed to Linnaeus after Italian women who used the drops made from Atropa to dilate their pupils to make themselves more beautiful, belladonna, beautiful lady.

Belladonna is a perennial herbaceous plant in the Solanaceae family, native to Europe, North Africa, Western Asia and some parts of Canada and the United States.  The foliage and berries are extremely toxic, containing tropane alkaloids.  These toxins include scopolamine and hyoscyamine, which cause a bizarre delirium and hallucinations, and are also used as pharmaceutical anticholinergics.  The drug atropine is derived from the plant.

Belladonna is one of the most toxic plants found in the Eastern Hemisphere.  All parts of the plant are toxic although the root of the plant is generally the most toxic part but this can vary from plant to plant. The ingestion of one leaf by an adult can be fatal, the berries pose the greatest danger to children, they are attractive and have a slightly sweet taste, two to five berries can be fatal to an adult and one berry fatal to a child (some sources say more of the plant needs to be ingested but I think this is a good number). The plant is also toxic to many domestic animals causing narcosis and paralysis.  This does not apply to cattle and rabbits, horses, goats and sheep that eat the plant seemingly without suffering harmful effects and then spread the seeds through their feces.

Though today we understand the risks involved in using deadly nightshade outweigh any potential benefits, it has a long history in medicine and cosmetics, and as a weapon.  Ancient Romans harnessed the effects of the plant to make poison-tipped arrows guaranteed to kill, and still others found it an effective anesthesia for surgery, as numbness and drowsiness are side effects of its toxic mix.

Belladonna is rightfully known as the plant used most throughout the history of stealth assassination.  Spies, as well as taste-testers hired by kings and the wealthy to sample for poisons, learned that it’s possible to develop a tolerance to belladonna.  By exposing himself to the toxins by taking small sips of a brew made from the plant over time, an assassin could demonstrate a drink was safe to consume and then his mark would swallow the poison willingly.  Made from the berries such a drink retains a sweet taste, and can pass as a fermented beverage.  According to history Scotland’s King Duncan I, in 1030, passed around bottles of the deadly drink to an army of Danes and killed them all without his having to lift a sword.  For so called witches, belladonna is the supposed main ingredient allowing broomsticks to levitate.  And perhaps it did, in their hallucinations.

Belladonna is difficult to grow in home gardens.  Some home gardeners plant it for its large, colorful display of berries, but remember:  This beauty blooms with no printed warning signs, caution is the watch word! 


Submitted by Pam Harris