Growing Potatoes for People and Animals in Finland

When the first potatoes arrived in Europe from South America in the 16th century, no one could have imagined the profound influence this inconspicuous tuber would one day have. Initially considered an ornamental plant, later a "poor man's food," it is now an indispensable part of our cuisine. The potato is an important part of culinary culture not only in Switzerland but also in Finland.

For us personally, the potato is far more than a staple food. Along with wood and eggs, it's one of the few products we hardly ever need to buy anymore. When we moved to Finland in 2023 and started planning our garden, it was clear to us that potatoes would make up a large part of our winter supply. In the first year, they were still part of the vegetable garden. However, due to the large quantities we grow, we have now prepared a separate field for them.

The preparation

Although we now continue to grow our own tubers, we wanted to start our new venture in Finland under the best conditions. Therefore, we ordered seed potatoes from a Finnish organic supplier. About three weeks before planting, we place the potatoes in a bright location with a temperature of 10–15°C and mist them with water daily. This encourages them to sprout. The soil is usually warm enough for planting by the end of May or beginning of June. It should be at least 10°C for the plants to grow well.

Setting

Potatoes are heavy feeders, meaning they draw a lot of nutrients from the soil. Soil fertilized with manure or compost helps the plants develop many large tubers. When planting, we keep a foot's distance between the tubers, adding a handful of compost between them. The seeding depth is about 10 cm. We leave about 60 cm between the rows to ensure the plants are well-ventilated later. After planting the tubers, we cover the soil at ground level.

Only when the plants are about 30 cm tall are the potatoes mounded. To do this, we take some soil from the left and right of the plant and cover it about two-thirds deep. This creates the typical ridge-like structure of potato cultivation.

The dam helps the potato in several ways:

• Nodule formation at the buried leaf bases

• Faster warming of the soil

• Storage of water between the dams when they were built across the slope

• Better soil aeration

• Easier harvest

Depending on the size of the area and the soil conditions, planting and mounding the soil is a very strenuous task. Our soil here is very clayey and stony. Often, large lumps of earth must first be broken up to form attractive mounds. Digging with a hoe and spade also takes time.

We plant approximately 120 m² with 400 tubers, which takes two people about 1.5 days. Since we prefer to work without machinery, we make sure the work is as back-friendly as possible.

Since Finnish summers are relatively rainy, despite temperatures sometimes reaching 25 degrees Celsius, we plant our tubers far apart to prevent fungal diseases like late blight. Good ventilation ensures that the plants dry out more quickly after a rain shower and that the heat doesn't build up too much under the canopy. We don't have any pests like the Colorado potato beetle at the moment. So far, we've only had problems with wireworms and hungry mice.

The harvest

The growing season in our region is relatively short. The potatoes have to be harvested again in early to mid-September. However, since we have up to 22 hours of daylight in summer, this balances things out.

For potatoes to be easy to store, they need to be skin-tight—that is, they need to have developed a firm skin. This happens when the leaves have died or been cut back, which takes about three weeks.

Here, night frosts can occur as early as mid-September, so we have to cut the leaves by mid-August at the latest. If the leaves are healthy, they go on the compost heap; otherwise, we move them to a wooded area far away from the garden.

During harvesting, it's important that the soil is slightly dry. Damaged tubers should be sorted out immediately and used as soon as possible. The harvested potatoes are then dried for a few days in a dark room at approximately 15 degrees Celsius. Afterward, we sort the tubers again, set some aside for planting next year, and pack them in bags. We store them in a dark natural cellar at approximately 5–12 degrees Celsius. The potatoes should be able to be stored for several months. To preserve the natural protective layer, the stored potatoes must never be washed.

170 kg of potatoes, despite everything

Every gardening year is different, and each one brings new challenges. There are many factors we can't control, so we just have to try to make the best of the situation. Last year, it was problems with machinery and late blight that caused us problems. This year, we had to contend with a very long dry period. Despite everything, we were able to harvest around 170kg of potatoes this year. Theoretically, that's enough for us for a whole year. Since the potatoes start to go bad in April, we have to find other ways to use them. Among other things, we feed our ducks boiled potatoes, but there's always the option of canning potatoes.

While it's physically demanding, it's also incredibly satisfying to know that with just a few days' work, you can grow a large portion of your own food.