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What Parts of Potato Plants Are Poisonous?

February 4, 2020

There is often some truth in old superstitions. Once thought deadly poison, 1 part of the nightshade family, the tomato (Lycopersicon esculentum), is one of the most-planted plants in the modern house garden today that its biochemistry is well known. Among tomato’s family members, potato (Solanum tuberosum), was never quite as infamous. As prevalent as they may be on menus, however, potato plants also contain toxins which could make you sick.


Potatoes are members of the Solanaceae plant familymembers, a collection that comprises many different plants variously regarded as weeds, ornamentals and vegetables or fruits. Belladonna, mandrake and tobacco are members of the category, also known by their common name, nightshade. Edible nightshades include peppers (Capsicum spp.) , eggplant (Solanum melongena) and huckleberries (Solanum melanocerasum). Like several other edible members of the family, potatoes contain alkaloids, which can be nitrogen-containing natural compounds. Among them, solanine, is toxic to humans and many animals.

Solamine in Potato Plants

The shrubby potato vine that grows above ground blooms like its cousin, the tomato. Small white, star-shaped flowers bloom in clusters and are followed by dark, berrylike fruitsand vegetables. These fruits and also the tissue of the shrubby plant which bears these are as filled with solamine as any weedy nightshade. Perhaps the production of solanine was an advanced defense for plants such as black nightshade (Solanum nigrum) and other weedy plants to ward off vegetarian grazers. The region of the potato you consume grows underground and comprises much less solanine. The solamine in potato tubers rests beneath the skin.

Potato Tubers

The thick tubers that grow in the plant’s root system contain little solamine cooking and — further decreases its own levels. When the tuber is exposed to mild, it begins producing chlorophyll — and solamine. The more light the tuber gets, the more chlorophyll it creates. Green flesh or skin on a potato or sprouts in the eyes which dimple its own skin sign rising levels of solamine that accompany the growth of a new plant. Potatoes which have been held at the low light of a grocery store create bin may start growing if they sit long enough

Safe Practices

Solamine may cause gastric distress, headache, delirium, shock, paralysis and, occasionally, more serious issues. Obviously, eating any component of the potato plant could be foolhardy. Eating a potato that’s been stored in a warm, light environment, and it has begun to develop green flesh or skin — or is sprouting — may also lead to problems. Cut off little green places and sprouts before cooking or discard the whole tuber if its symptoms have evolved to the point where its only value is as a supplier of chittings (fresh potato starts) for the garden. When growing potatoes from the backyard, mound the plants using mulch to maintain the tubers fully shaded, adding thickness as the season wears on. Solanaceae should never grow in exactly the exact same soil for two or more seasons and, after crop, they should be held in cool, dark storage.

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