Italian scientists are experimenting with growing vegetables in underwater greenhouses, where the temperature and humidity are ideal, while avoiding pests and not requiring land space.
Growing Vegetables Under the Sea
The project, named Nemo Garden, is the first and only underwater greenhouse in the world. Nemo Garden takes advantage of favorable environmental conditions under the sea, such as stable temperatures, CO2 absorption, and natural pest control to create a suitable environment for mass production of clean vegetables, according to Euronews Green.
Biomes used for planting in Nemo Garden. (Photo: Nemo Garden)
Nemo Garden holds significant importance for the future of Earth as the garden is specially designed for areas where environmental, economic, or morphological factors make cultivation challenging. The world will need to provide food for a population of 9.3 billion by 2050 amidst increasingly unstable climate conditions, according to the United Nations. The research team behind the project believes that underwater farms could provide food for coastal populations.
The underwater greenhouse resembles a cage, firmly anchored to the seabed at a depth of about 6 meters below the surface. Here, experts will pump air into the greenhouse and install soil trays for planting.
Unlike terrestrial greenhouses that require a lot of energy to maintain temperature and humidity for plants, the underwater greenhouse naturally maintains optimal conditions. The surrounding seawater helps keep the temperature stable regardless of day or night. Seawater evaporates, condenses on the top of the cage, and then flows down to the trays, providing sufficient water and maintaining ideal humidity at 83%.
Nemo Garden’s underwater planting. (Photo: CNN).
Under the sea, no climate changes such as droughts, floods, or frosts can affect the growth of crops. Additionally, these areas are completely free from harmful insects, meaning that no pesticides are needed.
Currently, they are growing some basil, several types of beans, and a few strawberries while waiting for harvest.
Nemo Garden uses hydroponics, a technique that uses nutrients in water instead of soil. This method is also applied in most vertical farms indoors. Sunlight reaches the plants, but growth stimulation lights are also turned on when needed. Everything is monitored on land through cameras and sensors. Settings can be adjusted remotely from anywhere in the world.
At harvest time, divers will cut the vegetables, place them in bags, and bring them to the surface. Due to its only two-meter diameter, the biomes cannot grow larger crops like corn or wheat. However, the structure can accommodate 70 to 100 small plants.
Technically, each biome contains about 20,000 liters of air above the water’s surface. Sunlight flowing through the water outside the biome warms the air inside. When there is little natural light underwater, LED lights attached to the surface of the biome provide additional illumination. The surrounding water helps maintain the internal temperature of the structure stable day and night while the processes of evaporation and condensation continuously supply fresh water to the crops.
Natural studies ranging from pharmaceuticals to culinary uses have been conducted at Nemo Garden. A 2020 study by the University of Pisa concluded that the basil plants in the garden have high essential oil density and contain more antioxidants. Co-founder Luca Gamberini stated that the underwater farm also attracts various marine life, such as fish.
The underwater farm also attracts various marine life, such as fish. (Photo: CNN).
The experimental project also faces many challenges, particularly from the weather. In 2019, a strong storm damaged several biomes. Besides natural disasters, building a farm in a harsh environment is not an easy task.
The staff at Nemo Garden are planning to build larger biomes in the future and set up additional farms elsewhere. To test feasibility in different environments, they intend to establish a small-scale version in a cold-water quarry in Ohio, USA, this year. Gamberini believes the technology can be adjusted for almost any environment.
Nemo Garden is supported by Siemens Digital Industries Software, allowing researchers to monitor the biome remotely and enhance production cycles and scalability. After demonstrating the effectiveness of the design, the research team is embarking on exporting the technology to other countries. In fact, biomes have already been built in Belgium and the Florida Keys, USA. The ultimate goal of the research team is to minimize product costs as much as possible.
