Which nightshade plants are toxic?

The nightshade family (Solanaceae) contains over 2,700 species, but it is a handful of notorious members that give the group its dangerous reputation. Knowing which nightshade plants are toxic is crucial for gardeners and pet owners alike, as some can be deadly while others, like tomatoes and potatoes, are staples of our diet.

Quick Summary

This guide details the specific nightshade plants that are poisonous, focusing on extremely dangerous species like deadly nightshade and jimsonweed. It explains the toxins present, identifies key characteristics, and highlights precautions for common edible nightshades to ensure safety.

Key Points

• Deadly Nightshade (Atropa belladonna) is extremely poisonous: The berries and foliage contain potent tropane alkaloids that can be fatal if ingested, particularly by children.

• Jimsonweed (Datura stramonium) is highly toxic: All parts of this plant, especially the seeds, contain dangerous alkaloids and can cause severe hallucinogenic and anticholinergic effects.

• Bittersweet Nightshade (Solanum dulcamara) is a poisonous vine: This common climbing vine has toxic red berries and leaves, containing solanine that causes gastrointestinal issues.

• Green potatoes and sprouts are toxic: The green parts of potato tubers and the sprouts contain solanine and should not be eaten.

• Tomato leaves and stems are toxic: While the fruit is safe, the green parts of the tomato plant contain alkaloids that are harmful in large quantities.

The nightshade family, or Solanaceae, is a vast and varied botanical group containing many popular food crops alongside some of the most poisonous plants in the world. The danger comes from naturally occurring alkaloids, such as atropine, scopolamine, and solanine, which vary significantly in concentration and effect across different species. While the ripened fruits of many species are harmless, other parts of the plant often contain toxic levels of these compounds.

Highly Toxic Nightshade Plants

Deadly Nightshade (Atropa belladonna)

This infamous plant is native to Europe and Western Asia and is one of the most toxic known.

• Appearance: A bushy perennial with dull green, oval-shaped leaves and bell-shaped, dull purple flowers. The berries are shiny and black when ripe, containing numerous seeds, which can be mistakenly ingested by children.
• Toxins: Contains tropane alkaloids, including atropine and scopolamine, which can cause delirium, hallucinations, blurred vision, and cardiac and respiratory failure.
• Danger Level: All parts are extremely poisonous, with as few as two berries potentially being fatal to a child.

Jimsonweed (Datura stramonium)

Also known as devil's apple or thorn apple, jimsonweed is found in many parts of the world and is highly toxic.

• Appearance: A fast-growing annual with spiny seed pods and large, trumpet-shaped white or purple flowers. The leaves are large, toothed, and have an unpleasant smell when crushed.
• Toxins: Contains the same tropane alkaloids as deadly nightshade (atropine, scopolamine, hyoscyamine), which produce powerful hallucinogenic and dangerous anticholinergic effects.
• Danger Level: The seeds contain the highest concentration of toxins and are extremely dangerous if ingested.

Bittersweet Nightshade (Solanum dulcamara)

This woody, climbing perennial is widespread across North America and Europe and should not be confused with deadly nightshade.

• Appearance: A vine-like plant with purple, star-shaped flowers and bright red berries that grow in clusters.
• Toxins: Contains solanine, a glycoalkaloid that is most concentrated in the unripe berries and leaves.
• Danger Level: The berries are toxic to humans and pets, and the plant can cause severe gastrointestinal upset.

The Toxicity of Common Edible Nightshades

It's important to understand that even common food crops in the nightshade family can be toxic if consumed incorrectly.

Potatoes (Solanum tuberosum)

Potatoes are safe to eat, but specific parts of the plant can be harmful.

• Toxic Parts: The sprouts, stems, and any green-skinned parts of the tuber contain solanine. This green coloration is a sign of chlorophyll production triggered by light exposure, indicating a higher level of alkaloids.
• Caution: Always remove any green spots or sprouts from potatoes before cooking. Composting affected potatoes is the safest practice.

Tomatoes (Solanum lycopersicum)

The fruit of the tomato plant is perfectly safe and nutritious, but the rest of the plant is not.

• Toxic Parts: Tomato leaves and stems contain alkaloids like tomatine and solanine, which are toxic in large quantities.
• Caution: While minor exposure is unlikely to cause serious harm, it is wise to avoid eating tomato leaves or stems and to wash hands after gardening.

Comparison of Toxic Nightshades

Feature	Deadly Nightshade (Atropa belladonna)	Jimsonweed (Datura stramonium)	Bittersweet Nightshade (Solanum dulcamara)
Toxin	Tropane alkaloids (atropine, scopolamine)	Tropane alkaloids (atropine, scopolamine)	Solanine, dulcamarine
Appearance	Bushy perennial, purple flowers, black berries	Annual herb, trumpet-shaped flowers, spiny seed pods	Woody vine, purple star-shaped flowers, red berries
Toxicity Level	Extremely high (potentially fatal)	High (potentially fatal)	Moderate (causes gastrointestinal issues)
Toxic Parts	All parts, especially berries and roots	All parts, especially seeds	Unripe berries and leaves
Symptoms	Delirium, hallucinations, blurred vision, convulsions	Hallucinations, confusion, tachycardia, seizures	Vomiting, diarrhea, drowsiness

How to Handle and Identify Safely

• Learn to identify: Familiarize yourself and your family with the appearance of the most dangerous nightshades, especially those that grow wild in your area. Use guides from authoritative sources like university extensions or forestry services.
• Wear protective gear: When handling unknown or wild plants, especially those resembling nightshades, wear gloves to avoid contact with sap, which can cause skin irritation.
• Supervise children and pets: Children and pets are most at risk of accidental poisoning from attractive berries. Teach children never to eat berries or flowers they find outdoors without an adult's approval. The ASPCA also lists many nightshades as toxic to pets.
• Prevent growth: Control invasive species like bittersweet nightshade in your yard. Its dense growth can shade out native plants and spread easily.
• Know the difference: Ensure you can distinguish between toxic look-alikes. For instance, bittersweet nightshade berries are red and in clusters, unlike the single, black berries of deadly nightshade.

Conclusion

While the nightshade family is home to many harmless culinary staples, the presence of highly poisonous relatives demands caution and knowledge. By understanding which specific plants and which parts are toxic, individuals can ensure safety in their gardens and natural surroundings. The extreme toxicity of plants like deadly nightshade and jimsonweed warrants immediate medical attention if ingested, while careful handling of edible nightshades is a prudent, everyday practice. Education is the best defense against accidental poisoning, protecting both human family members and beloved pets.

What to Do in Case of Ingestion

If you suspect that a toxic nightshade plant has been ingested, act quickly. Do not wait for symptoms to appear.

1. Remove any plant material from the person's mouth and save a sample for identification if possible.
2. Call a poison control center immediately. The number for the American Poison Control Center is (800) 222-1222. Provide them with the name of the plant if you know it.
3. Monitor symptoms and follow the instructions given by the poison control center or medical professional. Never induce vomiting unless instructed to do so by a professional.

Which nightshade plants are toxic? A Summary

• Atropa belladonna (Deadly Nightshade): All parts are highly poisonous; black berries are a particular danger.
• Datura stramonium (Jimsonweed): Extremely toxic; seeds have the highest concentration of dangerous alkaloids.
• Solanum dulcamara (Bittersweet Nightshade): Berries and leaves are toxic, causing gastrointestinal distress.
• Potato (Solanum tuberosum): Green parts and sprouts are toxic due to solanine.
• Tomato (Solanum lycopersicum): Leaves and stems are toxic, though the ripe fruit is not.

Protecting your family and pets from these risks starts with awareness and vigilance.

For more information, visit the National Institutes of Health website. [https://www.ncbi.nlm.nih.gov/]

Frequently Asked Questions

Are all plants in the nightshade family poisonous?

No, not all plants in the nightshade family are poisonous. The family includes common foods like potatoes, tomatoes, and eggplants, which are safe to eat, though care must be taken with certain parts, like potato sprouts and tomato leaves.

Can I eat ripe black nightshade berries?

This is very risky because black nightshade (Solanum nigrum) can be confused with the extremely poisonous deadly nightshade (Atropa belladonna). While some black nightshade species are edible when fully ripe, the potential for a fatal mistake makes consuming wild black berries unwise.

What happens if a pet eats deadly nightshade berries?

Deadly nightshade is highly toxic to pets, causing symptoms like dilated pupils, confusion, and paralysis. Immediate veterinary care is necessary, as ingestion can be fatal.

Is it safe to eat green tomatoes or unripe peppers?

Green tomatoes and unripe peppers contain higher concentrations of solanine and tomatine. While cooking can reduce the toxicity in green tomatoes, eating them raw or in large quantities is not recommended and can cause gastrointestinal distress.

What are the common signs of nightshade poisoning?

Symptoms of nightshade poisoning can include dilated pupils, blurred vision, confusion, hallucinations, dry mouth, rapid heart rate, and gastrointestinal upset. Severe cases can lead to convulsions, respiratory failure, and death.

How can I tell the difference between deadly nightshade and bittersweet nightshade?

Deadly nightshade (Atropa belladonna) has single, black berries and bell-shaped purple flowers. Bittersweet nightshade (Solanum dulcamara) has clusters of bright red berries and star-shaped purple flowers with yellow anthers.

What is the best way to handle wild nightshade plants in my yard?

If you are certain a plant is toxic nightshade, wear protective gloves and clothing when handling it. Thoroughly remove the entire plant, including the roots, to prevent regrowth. Dispose of the plant safely in sealed bags and wash your hands and tools thoroughly afterwards.