Potato, Solanum tuberosum
Global area: 17.4 million hectares
Global Field area: 21 m² (1.1 %)
Region of origin: South America
Main cultivation areas: China, Russia, India
Uses / main benefits: Food, starch, alcohol, animal feed
As a nightshade plant, the potato is a relative of the tomato. In its native Latin America, it is grown in all colors, sizes and shapes. From there, it was brought to Europe by Spanish sailors in the 16th century and subsequently made a significant contribution to overcoming hunger in regions of Europe that were overpopulated at the time.
A frugal plant
The annual to biennial herbaceous plant grows bushy to a height of approx. 30 to 50 cm. The flowers are white or purple and grow at the end of a shoot. Underground side shoots of the shoot end with five to twenty tubers, which are genetically identical to the mother plant and serve as storage organs. Tomato-like green berries about one centimeter in diameter develop from the flowers. The berries contain many seeds that can remain germinable for over ten years. Potatoes reproduce asexually (vegetatively) as well as sexually. In vegetative propagation, the tubers are placed 5 to 10 cm below the soil. Shoots grow from the buds on the potato tubers, forming shoots and roots. In sexual propagation by pollination of the flowers, self-fertilisation predominates. There are early, medium and late potato varieties, which differ in their growth period. Early potatoes are harvested after 90 days at the earliest and late potatoes after up to 180 days.
Potatoes are flexible and frugal plants and are therefore grown all over the world. They grow from sea level up to 4700 meters above sea level, have moderate water requirements and can also cope with cool temperatures and poor soils. However, climate change is now having a massive impact on them – with ever higher soil temperatures, persistent drought on the one hand and flooding on the other. The weakened plants are more susceptible to fungal diseases (brown rot) and pests such as the Colorado potato beetle.
The path to the staple food
In the Andes, the potato, a crop from the nightshade family, has been consumed for around 10,000 years. It was cultivated for the first time around 4,000 years ago. However, those wild forms did not have much in common with today’s potatoes, as the roots were only the size of a hazelnut and tasted ‘scratchy’ due to their high solanine content. To preserve the roots, they were freeze-dried by the Incas: they were laid out to dry for a few days in the cold nights and pressed with their feet during the day to squeeze out all the water. In this way, the tubers were preserved for years and were even used as currency.
Potato? No, thank you!
Around 1560, Spanish conquistadors brought the tubers to Europe for the first time, in their luggage. At sea, they were a valuable foodstuff as they were easy to store and prevented scurvy thanks to their vitamin C content. On the European mainland, however, people knew little about this exotic plant. Although it was given to royal houses for their botanical gardens because of its beautiful flowers, it was rejected as a foodstuff. There were various reasons for this: As a nightshade plant, it was considered a ‘witch’s plant’, like belladonna or mandrake, as it has an intoxicating or deadly poisonous effect depending on the dosage. Most people were unaware that only the cooked brown roots, but not the above-ground parts of the plant, should be eaten. The fruits that the potato plant produces after flowering were also deceptive: If they are eaten, nausea and poisoning are inevitable. Moreover, the potato is not mentioned at all in the Bible, which reinforced the reservations. However, the tuber did have advocates, such as Great Britain’s Royal Society, which pointed out its value in the fight against hunger as early as 1660, or Landgrave Wilhelm IV of Hesse-Kassel, who wrote in 1591:
‘These, when cooked, are very pleasant to eat’. – Despite everything, the tuber initially only ended up in the pig trough.
The cunning of the ‘Old Fritz’
Even 200 years after its arrival in Europe, the potato had not caught on. Frederick the Great was aware of the nutritional quality of the potato and initially tried to spread it by distributing seed tubers. However, when success failed to materialise and a serious hunger crisis loomed – due to population growth and war – the king resorted to decrees and controls. According to legend, ‘Old Fritz’ resorted to a ruse to convince the farmers: he had his own fields guarded by soldiers, but deliberately allowed thefts to take place. What was so valuable to the king had to be tasty for the common people too!
Triumph and blows of fate
In the end, acute hunger helped the potato to victory, which Frederick II himself did not live to see. From the middle of the 18th century, the tuber was so widespread that it made a decisive contribution to the economic upturn of the European continent. The increased food supply (the potato grows easily even on poor soils and provides two to four times as many calories as grain on the same area of land) also increased the population, in some countries to such an extent that they became dependent on the potato. In Ireland, the spread of the potato blight, a fungus introduced from North America, led to a famine in the middle of the 19th century that halved the island’s population within a few years – those who did not want to starve emigrated, mainly to America.
The best potato sayings
Pulling the potatoes out of the fire for someone (Germany): It’s handy when someone takes an unpleasant task off your hands.
Drop somebody or something like a hot potato (Great Britain): If you quickly get rid of an unpleasant thing or person, you drop it or them like a hot potato.
No entender ni patata (Spain): If you don’t understand something in Spain, then ‘you only understand potato’.
Vai plantar batatas! (Portugal): In Portugal, people who are supposed to disappear are advised to plant potatoes.
Avoir la patate (France): When the French say that they ‘have a potato’, they mean that they are fit, full of energy and in shape.
All over the world
At the beginning of the 17th century, potatoes were also grown to a significant extent in England and Ireland. Emigrant families eventually brought the potato to North America, Scandinavia and Russia. It probably came to China from the Philippines in the 16th and 17th centuries, where it was brought by the Spanish conquistadors.
Today, the potato is an important staple food after rice and cereals. Over a billion people eat the tuber – in 2022, around 375 million tons were harvested worldwide. Around a third of the world’s potatoes are now grown in China, followed by India, Ukraine, Russia and the USA with significantly smaller quantities. In China, the potato has traditionally been eaten as a ‘vegetable’ rather than a staple food. However, in 2013, the Chinese government began a strategy to establish potatoes as a staple food. This was intended to serve China’s food security and sovereignty. Since then, potato bread, potato noodles, potato cakes and other processed forms of the potato have also made it onto the market in China. However, potatoes are still mainly eaten fresh and the world-famous French fries are becoming increasingly popular.
Is the potato healthy?
There are around 7,000 different potato varieties, some of which are also used as industrial and fodder potatoes, as well as 180 wild varieties.
Potatoes contain up to a quarter of carbohydrates in the form of starch, which is an important source of energy. If we eat too much, the excess energy is stored in our body as fat. Potatoes also contain many minerals such as sodium, magnesium, calcium, iron, high-quality protein and a good portion of potassium. Potatoes are also rich in B vitamins and the important vitamin C. 100g of potatoes contain 17mmg of vitamin C. An apple contains just 4.6mmg of the same amount. However, most of the nutrients are directly in or under the skin – it is therefore recommended to eat the skin with organic potatoes. Incidentally, the conventional potato consists of a good 77% water and, at 70kcal per 100 grams, is lower in calories than is often said.
The starch in the potato also makes it possible to produce vodka: the starch molecules are broken down by mixing and heating with water, resulting in a sweet mash. Yeast is then used to start the fermentation process, which converts the sugar in the mash into alcohol.
The question of processing naturally plays a central role in assessing the healthiness of potato consumption: freshly cooked in water, the potato is healthier than highly processed foods such as potato potato chips or deep-fried in oil as chips. Of course, it is also not healthy in the form of vodka.
However, be careful with green potatoes – they contain several times more alkaloids, especially solanine, and should therefore not be eaten.
Sources
ARD Alpha: The triumph of the devil’s tuber
Wang et al (2021): Potato Processing Industry in China: Current Scenario, Future Trends and Global Impact. Potato Res. 66, 543-562 (2023). Available here.