The world is in the grip of a food crisis. In many parts of the world, farmland is no longer cultivable due to the overuse of pesticides, droughts and extreme weather events brought on by a changing climate. Good-quality soil for growing crops to feed the swelling global population is becoming more scarce.
So, is there a way to produce food without the need to use soil? Several companies are doing just that, using a variety of methods such as growing crops underwater, using nutrient-rich moisture, or by reusing coffee grounds as fertiliser.
There are a few well-established methods, such as aeroponics, where the roots of the plants hang suspended and are sprayed with a nutrient-rich mist. Another is aquaponics, where fish are farmed alongside plants, and their waste-products are used to nourish the plants.
Not only does being able to grow food without the need for soil have implications for growing crops on Earth, it could also be key to sustaining our stay on the Moon or
Mars. Being able to grow plants without soil will be key to having a reliable food source and helping us maintain a presence on other planets.
In this gallery, we bring you some of the projects that show that it is possible to grow food in a way that is sustainable and kinder to the environment.
Edo Radici Felici, Italy Edo Radici Felici's facility at Quarrata, Italy, uses a tailor-made system of aeroponics to grow various vegetable species. Aeroponics is an alternative method of growing plants by suspending their roots in the air and irrigating them with a nutrient-dense solution, thus eliminating the need to use soils. In this image, Leonardo Lenzi, partner and head of research and development at Edo, checks the lettuces before they are harvested and sent to the market at Coldiretti. Photo by Vittoria Lorenzetti/Parallelozero This image shows a section of the structure of the floating system. The plants have a life cycle of 18 days from planting to harvest. The roots hang in the air and are fed by an irrigation system with nozzles that spray nutrient substances onto the plant. Photo by Vittoria Lorenzetti/Parallelozero Hydroponic village, Indonesia A child walks down an alley with hydroponic vegetables on one side in Lolu Village, Palu, Central Sulawesi Province, Indonesia. The village is dubbed as Hydroponic Village because almost all households grow vegetables using a hydroponic system (the process of growing plants in liquid instead of soil), either for their own consumption or for sale. The Indonesian government encourages its citizens to use their home yards by growing crops using a hydroponic system as an effort to improve food security following the COVID-19 pandemic. Photo by Basri Marzuki/NurPhoto/Getty Images A detailed image of food being grown by residents using hydroponic methods in Lolu Village, Palu, Central Sulawesi Province, Indonesia. Photo by Basri Marzuki/NurPhoto/Getty Images Zero Farms, Italy Anna Mastellaro and Anita Bonotto, agronomists in the Zero M facility at Zero Farms in Pordenone, Italy, check batches of basil, chives, mizuna and other vegetables. All the plants are grown in aeroponic facilities without the use of soil or substrates. Instead of using costly large industrial buildings, Zero uses a system of modular units which can be easily installed on a smaller scale. Photo by Vittoria Lorenzetti/Parallelozero Biologist Francesco Dose works with mint cuttings from the experimental aeroponic system at Zero Farms, Pordenone, Italy. Photo by Vittoria Lorenzetti/Parallelozero National agricultural demonstration zone, China Victor Lo checks the water filtration system at his aquaponics production base in the national agricultural demonstration zone in Kaiping City, Jiangmen, China. Lo, Fung Leung and Mandy Tam came to the Kaiping national agricultural demonstration zone to research aquaponic methods of growing. During five years of research, the team managed to solve many problems associated with this system, and have applied for nearly 10 patents. To date, the base annually yields some 300 tonnes of organic vegetables, most of them sold to Hong Kong. Photo by Xinhua/Shutterstock Nemo's Garden, Italy Nemo's Garden in Noli, Italy, is an underwater garden located at a depth of 6-10 metres. It is composed of six plastic biospheres measuring two metres in diameter, and employs a hydroponic cultivation method to grow basil plants. The garden is designed to have a minimal impact on the local marine life, and also does not require any energy sources other than the Sun. Photo by Vittoria Lorenzetti/Parallelozero Herbs growing in the underwater biospheres of the Nemo project, which are anchored to the sea bottom. The project was started in 2012, and now houses more than 300 plants grown with an automated hydroponic system. The main herb grown is basil but experiments are also carried out with mint and liquorice. Photo by Alessandro Rota/Getty Images Upward Farms, USA Upward Farms uses modern vertical farming techniques in conjunction with aquaponics, therefore growing crops in a complete ecosystem. Fish swim directly below these plants, which absorb nutrients from fish waste. The plants filter the water as they grow, thus reducing water use by 95 per cent. The crops and seafood produced here are exported around the world. Photo by Upward Farms More images from Science Focus: Circle Food & Energy Solutions, Italy The Circle Food & Energy Solutions is a farm on the outskirts of Rome. Here, with their vertical aquaponic systems housed in tents in the Italian countryside, this small company is able to grow a variety of edible crops without impacting on the environment. Aquaponics is a method of growing plants in water, using waste produced by fish and small marine creatures. The plants can extract the nutrients from this waste, and in turn can purify the water, therefore it is a system with almost no waste at all. Photo by Vittoria Lorenzetti/Parallelozero The aquaponic system enables the cultivation of baby leaves and aromatic herbs. The system is built in such a way as to let the water flow downwards from above, thereby transporting nutrients to the plants. The plants themselves then purify the water and release it into the containers below. Photo by Vittoria Lorenzetti/Parallelozero Crate to Plate, UK Sebastien Sainsbury, CEO at Crate to Plate, is pictured inside the company's urban farm near Elephant and Castle, London, UK. Housed within two shipping containers, the company uses hydroponic technology and nutrient-rich water to grow greens vertically in urban environments all year round. Photo by PinPep/Shutterstock Crate to Plate's urban farm near Elephant and Castle, London, UK. Photo by PinPep/Shutterstock Sofia's Strawberries, Italy Le fragole di Sofia (Sofia's Strawberries), in Crespino, Italy, grows and sells its own strawberries that have been grown using a soilless method in a specially constructed greenhouse. Sofia Michieli started to grow the strawberries on her parents' farm, and has since won awards for her innovation. Photo by Vittoria Lorenzetti/Parallelozero A ferti-irrigation system supplies drops of water full of nutrients onto the growing substrate. This type of system means only the water required for the plants is used, and excessive irrigation (and therefore waste) can be avoided. Photo by Vittoria Lorenzetti/Parallelozero