In the year 600 B.C.E., the climate in Western Asia along the Euphrates River was arid and hot, but lush gardens were climbing up the metropolis walls, Babylon. Babylon's Hanging Gardens are thought to have existed in a river pulley-water system; an irrigation practice known today as hydroponics. More precisely, hydroponics is the farming system where plants can be grown in nutrient-fortified water, rather than in soil. In light of concerns about feeding a rising human population in a changing world, scientists claim that hydroponic technology will alleviate the inevitable food shortages.
The need for innovative agriculture
The United Nations (UN) has expected the global population to reach nearly 10 billion people by 2050, with "about 83 million people added per year to the world's population until then." In 2019 alone, an estimated 124 million people were faced with severe food shortages from climate-related events such as floods, erratic rainfall, droughts and high temperatures. Given that hydroponics can grow food in a regulated climate, with less water and higher yields, the United Nations Food and Agriculture Organization has introduced hydroponic farming in areas of the world that are suffering from food shortages.
The technology used in the implementation of hydroponic systems in developing countries around the world is focused largely on hydroponic systems developed at NASA. Physicists and biologists came together in the late 20th century to find out a way to grow food in one of the best human-known climates: space. Physiologists at NASA 's aerospace plant started experimenting with growing plants on the International Space Station using hydroponics technology because it takes less space and fewer energy than traditional agriculture. In 2015 astronauts ate the first space-grown leafy vegetables after comprehensive experiments. When did NASA come up with the concept of using the technology in space? This was from a century of research by scientists who discovered that plants survived – and thrived – when grown in water.
Hydroponic gardening in modern time
Julius Sachs, a German botanist at the University of Würzburg, devoted his career in the 19th century to discovering the basic elements plants need to survive. Through analysing differences between plants grown in soil and those grown in water, Sachs found that plants do not need to grow in soil but require only the nutrients obtained from micro-organisms that reside in soil. In 1860, Sachs published the formula for growing plants in water called "nutrient solution" which laid the foundation for modern hydroponic technology
In 1937, Rd. W.E. Gericke, an American scientist, explained how this method of growing plants could be used to produce vast quantities of crops for agricultural purposes. Gericke and others showed that water's fluid dynamics modified the architecture of plant roots, enabling them to consume nutrients more efficiently than soil-grown plants, leading them to grow larger in a shorter period of time. Scientists have since optimized the nutrient solution, a combination of 13 macronutrients and micronutrients, that are applied to hydroponic farming water. Today, hydroponic systems are very sophisticated; there are devices that control the pH level of nutrients and the water temperature, and also the amount of light the plants obtain. There are three main types of hydroponic systems: a method for nutrient films, an Ebb and Flow system and a Wick system. A hydroponic nutrient film technique involves plants being grown in a growing tray that is slightly angled and mounted over a reservoir filled with the water-nutrient mix. It causes a thin stream of water to flow into the roots of the plants, allowing the plants to have enough water, nutrients and aeration, and then drain back into the tank.
The technique of nutrient film is the most common hydroponic method employed today. Plenty and Bowery, two of the largest hydroponic farms in the United States, use the techniques of nutrient film to cultivate lettuce, spinach and other leafy greens. The Ebb and Flow technique helps plants to flood with the nutrient-rich water, and after sucking up nutrients from the plant roots, water is quickly drained back into a reservoir for reuse. Finally, a hydroponic wick system is the simplest of all, because nutrients from a wick or piece of string running up to the plant from the water reservoir are passively supplied to the plant. In this method, plants are grown in an inert growing medium including balls of sand, rock, wool or clay that help to anchor the roots of the plants. Such multiple systems may be interchangeable, but certain systems may be best for growing different plant types.
There are also benefits of using any of those hydroponic systems. Second, there is no need to think about making a plot of property, weeds, pests living in dirt or treating the crops with pesticides, since there is no soil. Water is therefore highly conserved because of the storage of nutrients, as the same water can be used over and over again. Furthermore, since most of these hydroponic farms are indoors, food can be grown throughout the year, and even in the middle of a major city, like New York. With all these advantages, we may begin to see more hydroponic farms sprouting around the world, as this form of farming promises to revolutionize agriculture by using less water
Hydroponics for sustainable future
Given the need for more sustainable agriculture, there has been an increase in the number of environmentally friendly start-ups around the world using hydroponic technology to grow large-scale crops using a technique known as "vertical farming."
Vertical farms are buildings packed with countless levels of hydroponic systems (or planters in the nutrient film style), growing various crops in an indoor, temperature-controlled environment. Designed in Dubai, the largest vertical farm covers 130,000 square feet of land and aims to generate 6,000 pounds of food every day, "using 1/2500th the amount of water as an equivalent soil activity." It will greatly revolutionize the way the city eats for a city that imports 85 per cent of its food.
Although vertical farms hold a great deal of promise, they are costly to implement, technologically challenging on a large scale, and the food produced from such systems is typically more expensive than comparable soil grown food due to the high energy costs of maintaining the systems. Nevertheless, the Associated Press reports that food provided by hydroponic technology in 2020 amounts to US$ 32 billion, and this is expected to rise at a rate of 5 percent per annum until 2025.
Although hydroponic technology can never replace traditional farming, it breaks the food production paradigm; we can see a new generation of urban farmers building green walls within their homes or community centres to feed families with fresh produce grown throughout the year.