40 metres offshore from Noli in Italy’s Liguria region, divers come across some peculiar underwater domes that are moored to the ocean floor. The project, also known as Nemo’s Garden, is the world’s first underwater greenhouse. Here, a team of researchers are growing over 100 different fruits, herbs, flowers, and vegetables in futuristic underwater bells.

The project started with Sergio Gamberini, president of Ocean Reef, a dive equipment manufacturer, when he asked himself where the best conditions for growing basil could be found. The answer: In the ocean where there is enough water, and the temperature doesn’t fluctuate too much.

Obsessed with his idea, he started to build air-filled underwater domes with the help of his family, investing over 100,000 Euros of their own funds. The location for the project was carefully chosen and the domes ended up in a location where 30% of sunlight could still penetrate and the water has a constant temperature of around 20 degrees Celsius in summer. The ambitious plan seemed to pay off; in only seven weeks, basil seeds turned into proper plants that tasted just as good, if not better, than their land-grown counterparts.

The idea behind the glass domes is quite simple: Each dome is filled with approximately 20,000 litres of air that sits above a body of surface water, while the sun’s light naturally penetrates the water column and heats up the domes and the air within naturally.

On the inside, the sea water then evaporates on the dome wall, the salt settles, and freshwater begins to rain down on the plants, while the outside water maintains the temperature inside the dome throughout the day. For the plants to grow and not die, the conditions ​​in the domes must remain constant. In winter, when there is less natural light, attached LED lights act as an additional light source to grow the plants.

Growing food in these domes means that there is no need to water the plants, while no pesticides have to be used. While this project is still in its infancy, these biospheres could be useful in arid countries that don’t have much land or preferable conditions for agriculture. “Imagine all of the coasts, and all of the countries where there is enough water. I think in 10, maybe 20 years, we will have this technology all over the world,” enthuses Gamberini.

Nemo’s Garden could hold important insights for feeding future generations – especially in regions where economic or environmental factors make agriculture difficult. With the global population expected to hit 9.3 billion in 2050, and climate change posing more and more risks, feeding the ever-growing population is one of the biggest challenges of our time. But growing vegetables underwater on a large scale is still a vision as the production of the underwater vegetables is still very expensive. As an example: A gram of basil from the Mediterranean currently costs around 10 Euros while a gram of field-grown basil can be purchased for as little as five cents. “The price for our basil plants will never be comparable to what you pay in a supermarket. That being said, they come with a much-reduced environmental footprint,” adds Gamberini.

After the Nemo’s Garden team initially planted basil, they have since planted more than 100 different plants, including medicinal herbs, salad greens, beans, tomatoes, and strawberries. Interestingly, the team also found that the plants produced in the underwater domes were richer in nutritional content than those grown on land. In an article published by Modern Farmer, Gamberini said: “Theoretically, the project considerably increases the percentage of the world’s surface that could be used for growing crops, especially in countries where environmental conditions make growing plants difficult.”

Gianni Fontanesi, project coordinator at Nemo’s Garden, adds: “Every year, we are discovering new possible applications for the biospheres,” says Gianni Fontanesi, project coordinator at Nemo’s Garden. Some of these could include ecotourism, seaweed farming, as well as wildlife research stations amongst other ideas.

Only time will tell whether Italy’s underwater domes will provide food on a larger scale in the future. One thing is clear: A great start has been made by these courageous pioneers of underwater farming.