Are Potato Fruits Poisonous? Why You Should Avoid the Berry from Your Plant

December 16, 2025 •

4 min read

Did you know that the same plant that produces our beloved potatoes can also grow a highly toxic fruit? Belonging to the nightshade family, the potato plant sometimes produces small, green, tomato-like berries that are not safe for consumption and contain high levels of solanine.

Quick Summary

The small, tomato-like berries occasionally found on potato plants are poisonous due to high concentrations of the toxic alkaloid solanine. The tubers are safe, but the fruit, along with the leaves and stems, is toxic and should not be eaten by humans or pets.

Key Points

Potato Fruits Are Poisonous: The small, green, tomato-like berries that grow on potato plants are highly toxic and should not be eaten.
Solanine is the Toxic Compound: The berries contain high concentrations of solanine, a glycoalkaloid that can cause severe gastrointestinal and neurological problems.
The Tubers Are Still Safe: The poison in the fruit does not affect the edible tubers growing underground, as long as they are not green or spoiled.
Remove Berries for Safety: Gardeners should remove and dispose of the berries to prevent accidental ingestion, especially with children or pets present.
Avoid Misidentification: The potato fruit can be mistaken for other nightshade berries like those of bittersweet nightshade, which are also poisonous.
Symptoms of Poisoning: Ingestion can lead to symptoms such as nausea, vomiting, headaches, and diarrhea, and should be treated by medical professionals.

Yes, the Fruit of a Potato Plant is Poisonous

Contrary to popular belief, a potato is a tuber, not a root, and is an edible part of the plant that grows underground. The true fruit of the potato plant, Solanum tuberosum, is a small, green, tomato-like berry that forms after the plant flowers. This fruit is highly poisonous due to the presence of a toxic compound called solanine. It is important for gardeners and home cooks to understand this distinction to avoid accidental ingestion.

The 'Potato Tree' Misconception

The idea of a "potato tree" is a common misconception, likely stemming from confusion with other plants in the Solanum family. While a potato plant is a small, bushy herb, there are other species like the bittersweet or woody nightshade (Solanum dulcamara) that are perennial, climbing vines and produce red berries. Both the potato plant's green berries and the bittersweet nightshade's colorful berries are toxic. The term "potato tree" is not a botanical classification and should not be used to describe the fruit-bearing potato plant.

Why Do Potato Plants Produce Fruit?

It is actually uncommon for many modern potato varieties to produce fruit. Factors such as specific weather conditions (cooler, wetter summers), pollination, and certain varieties' genetics can lead to fruit production. When the plant flowers are successfully pollinated, they can develop into the small, green berries that carry the plant's seeds. In most cultivated potato plants, the energy is directed towards growing the edible tubers underground, meaning the flowers often drop off before forming fruit. However, gardeners should always be vigilant.

The Dangers of Solanine Toxicity

Solanine is a glycoalkaloid poison that is naturally produced by plants in the nightshade family as a defense mechanism against pests. While present in low, safe amounts in edible potato tubers, it is concentrated at much higher, toxic levels in the plant's leaves, stems, sprouts, and especially the green fruits. Solanine poisoning can cause both gastrointestinal and neurological symptoms. Symptoms can include nausea, vomiting, stomach cramps, headaches, and diarrhea. In severe cases, hallucinations, paralysis, and death have been reported, making the consumption of potato berries extremely dangerous.

Safely Managing Your Garden

If you find these berries in your garden, it is best to remove them, particularly if you have children or pets who might be tempted to eat them. Do not compost the berries where they might be accessible. If you choose to remove them, wear gloves and dispose of them safely. The presence of berries does not affect the safety of the tubers growing underground, so your potato crop remains perfectly edible.

Identifying Common Nightshade Fruits

To prevent any dangerous mix-ups, it's helpful to distinguish between different plants in the nightshade family. The following table compares the fruits of the potato plant, the common tomato, and bittersweet nightshade.


Feature	Potato Fruit (Solanum tuberosum)	Tomato (Solanum lycopersicum)	Bittersweet Nightshade (Solanum dulcamara)
Appearance	Small, round or oblong, green, resembling cherry tomatoes.	Varies by variety; typically larger, ripen from green to red, yellow, or purple.	Small, round, berries that ripen from green to orange to bright red.
Toxicity	Highly toxic; contains concentrated solanine.	Generally not toxic when ripe; leaves and stems contain low levels of alkaloids.	All parts are toxic; berries contain solanine and dulcamarine.
Plant Type	Bushy, herbaceous plant.	Trailing or upright herbaceous vine.	Perennial, woody, climbing vine.
Edibility	Not edible.	Edible when ripe; a culinary staple.	Not edible; poisonous.
Location	Grows on the leafy parts of the potato plant.	Grows on the tomato plant's vine.	Found on vines in hedges, woods, and disturbed areas.

Taking Precautions Against Solanine

Do not consume any part of the potato plant other than the edible tubers. This includes the leaves, stems, and especially the berries.
Remove any green, tomato-like berries from your potato plants. This prevents accidental consumption, especially by children or curious pets.
Store potatoes in a dark, cool place. Light exposure can cause tubers to turn green, which indicates an increase in solanine concentration. If a potato has green spots, it is best to cut them off before cooking.
Avoid eating any parts of other wild nightshade plants, such as bittersweet nightshade, as they are often highly toxic.

Conclusion

While the potato plant provides one of the world's most versatile food staples, it is vital to remember its roots in the nightshade family. The green, tomato-like berries produced on rare occasions are indeed poisonous and pose a significant health risk if consumed. By understanding the plant's toxicity and taking proper precautions in the garden, you can ensure a safe and successful harvest of the delicious tubers while avoiding the dangerous fruit. For more details on potato fruits and their toxicity, refer to resources from university extension programs(https://www.cultivariable.com/potato-what-you-should-know-about-fruits-on-your-potato-plants/).

Frequently Asked Questions

Potato plants produce fruit after their flowers are pollinated, which can happen under specific weather conditions, such as cooler, wetter summers. Many modern cultivated varieties are bred to focus energy on growing tubers rather than fruit, so berry production is relatively rare.

Yes, the edible potato tubers are perfectly safe to eat even if the plant has produced berries. The toxins are concentrated in the berries and the plant's green foliage, not in the tubers themselves, unless the tubers have turned green due to light exposure.

If a child or pet consumes a potato berry, it is considered a medical emergency. Seek immediate medical attention or contact a poison control center, as the high concentration of solanine can cause severe poisoning.

Although both are in the nightshade family and can look similar when green, a potato berry is highly toxic and grows on a potato plant. A tomato is the edible fruit of a different species (Solanum lycopersicum) and is non-toxic when ripe.

It is not recommended to compost potato berries. The seeds can remain viable for several years and may sprout, introducing new, potentially toxic plants into your compost pile or garden.

No, cooking does not effectively destroy solanine. High temperatures may reduce the level slightly, but not enough to render the berries safe for consumption. Do not attempt to cook or eat potato berries.

The most common indicator of high solanine levels in a potato tuber is a green tinge under the skin, which is caused by light exposure. A bitter taste is also a reliable sign of toxicity. You should cut away any green parts and avoid eating overly bitter potatoes.