Technology enables us to cultivate vegetables virtually anywhere, even in Norway or Alaska during an ice-cold winter. Or in the stiflingly hot desert of South Australia. Hydroponics at sea could be the next challenge for vegetable growers.
One of the nurseries having to deal with external conditions throughout the year is Viken Gartneri in Frosta, 50 miles north of Trondheim, Norway. There, Jonas and his wife Ragnhild and 13 staff members together cultivate 30 varieties of herbs in pots and two varieties of lettuce on water in a glasshouse spanning 13,000 m2. The outside temperature varies from over 25 degrees Celsius in the summer to minus 25 degrees Celsius in the winter. ‘The greatest challenge for us is the changing of the seasons. In the winter there’s pretty much no sunlight here, compared to 20 hours of sunlight in the summer. Moisture is another challenge here, due to the quantities of rain and snow we recieve. And the wind can get pretty stiff here too, which can damage the greenhouse’, says Jonas.
Cultivating in a fjord
The high-tech greenhouse is situated on a peninsula in a fjord, which tempers the extreme climate. It also results in greater light output. During the spring, the snow provides extra light reflection, adds Ragnhild, which presents a new challenge. Climate control in the greenhouse, which was produced by a Danish firm, is done with the aid of double glazing, a double climate screen and a Finnish computer. The climate screens stay completely retracted in the winter. They only open them very slightly to allow moisture to escape, with assimilation lights keeping the greenhouse at the right temperature when they do so.
Despite the challenges, Viken Gartneri succeeds in cultivating high-quality produce, which is sold to Norgesgruppen and Bama in central and northern Norway. These customers demand not only high quality but also swift delivery, says Ragnhild. ‘We work hard to ensure that we remain the most sought-after producer of lettuce and herbs in our sales territory. We’re also taking part in the research into new food trends and the development of production methods.’
Cultivating in the Arctic Circle
In Kotzebue, in north-west Alaska, vegetables are cultivated in a 12-metre-long container throughout the year. Different kinds of herbs and lettuce are harvested from the container on a weekly basis. They are also experimenting with kale. LED lights are suspended in the container, taking over the role of the sun. There are nearly 3,300 residents in the city, and they have given the new way of cultivating vegetables their seal of approval. It frequently takes two to three weeks before freshly harvested vegetables find their way to the local supermarkets. These are flown in from the more southerly regions in Alaska, over 600 miles away. Which results in a head of ‘fresh’ romaine lettuce in the shop costing as much as $8. ‘The project is a tremendous success’, says Joe Carr, the only professional vegetable grower in the Arctic Circle. ‘Each week we harvest 450 plants and they’re extremely popular. Before we came on the scene, fresh vegetables and herbs weren’t good-quality and were simply too expensive, or both.’
Profitability as a challenge
Kikiktagruk Inupiat Corporation, the parent company of Arctic Greens, is looking to set up containers for the vertical cultivation of vegetables throughout Alaska. Not just to offer the local population fresh food, but also to create jobs. One of the most significant challenges is the price tag. The set-up costs for the project in Kotzebue were in excess of 180,00 euros. The most significant expense is electricity, which is generated using diesel engines. With its artificial lighting eight hours a day and its heating 24 hours a day, the hydroponic system devours electricity, which is expensive in Kotzebue, just like it is everywhere in Alaska. It is partly because of this that the price of the vertically cultivated vegetables is on a par with the imported vegetables. Consequently the entrepreneurs are looking for ways to drive down their energy costs, by using wind energy or solar panels, for example.
Hydroponics at sea could be the next challenge for vegetable growers, particularly in dry coastal areas. The Ocean Reef Group spent five years experimenting with cultivating vegetables below sea level off the coast of Noli (Italy) using small, transparent balloons. The balloons have since been replaced with rigid acrylic biospheres measuring two metres in diameter.
The capsules from the nursery - called Nemo’s Garden - have been secured to the seabed. The biospheres are equipped with sensors, remote-controlled ventilators, cameras, Wi-Fi and intercom. Due to the fact that they let light through, the temperature in the capsules rise and the plants are given fresh water, which evaporates out of the sea and condenses on the walls. Pesticides are not necessary. Energy and water consumption is minimal too. The plants are harvested by divers, who regularly inspect the plants and systems. Experience has now been gained with 30 plants, including tomato, basil, lettuce and cabbage.
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