On the terraced hillsides of Liguria in Northern Italy, the fragrant scent of basil fills the air, much of it destined to be crushed in a mortar with olive oil, garlic, pine nuts, salt, parmesan and pecorino cheese to make traditional pesto Genovese. It’s little surprise that this leafy herb so entwined in the culinary heritage of the area has been chosen as the control plant for a pioneering project that can be found 50 meters off the coast of Noli, a fishing village an hour from the regional capital Genoa.
Called Nemo’s Garden, it is the world’s first—and only—underwater garden. Submerged at depths of up to 12 meters, a network of six domes, each home to around 60 seedbeds, sit on stilts anchored onto the ocean floor. This year marks a decade since the project was established by Ligurian scuba diving equipment manufacturer Ocean Reef Group, on the back of a casual conversation between company founder Sergio Gamberini and a farmer friend. “They spoke about connecting both of their worlds, agriculture and underwater technology,” says Luca Gamberini, Sergio’s son and Ocean Reef vice president of sales and marketing. Within a year, the first crop had sprouted. “We literally took a plant underwater and the seeds came right after that,” he says.
Inside each biosphere, as the domes are called, approximately 20,000 liters of air sit trapped atop a body of surface water. “Light from the sun travels through the water outside the biospheres to reach the air inside it and heat it up,” Gamberini explains. In winter, when there’s less natural light, LEDs connected to the surface by a power line provide an additional source of light. The water outside keeps the temperature inside stable day and night, and evaporation and condensation inside the dome ensure a supply of freshwater for the plants. “What we’re doing is very basic,” Gamberini says. “We’re just doing it underwater, and with a bit more difficulty.”
Some important lessons have been learned along the way. “At the beginning, we used soil, but we quickly realized there were too many complications,” he says. As well as the logistics and costs involved in its transportation to the biospheres, soil brings an increased risk of introducing disease, insects or parasites into the domes. The switch was made to hydroponics, and the seeds are now planted inside a plastic cone containing a substrate (such as coconut coir or rockwool). The crops are fertilized with hydroponic fertilizer.
Read the complete article at www.modernfarmer.com.