Many people think that hydroponics growing of plants is a recent phenomenon, but in actual fact, as mentioned in my handbook “Hydroponics 101”, its origins go back to the hanging gardens of Babylon and the floating gardens of the Aztecs in South America.
In Europe, during the 17th century, many scientists worked on experiments to show that a water-based growing system could be made to successfully grow plants. In 1860, Professor Julius von Sachs realised that salts of nitrogen, potassium, calcium, magnesium and other trace elements were what made the plants grow. This was the breakthrough for modern hydroponics.
During the Second World War the Americans, who are known for their innovation, had to feed their troops in the Far East and did not want to follow the practice in that part of the world of growing vegetables in what is euphemistically known as “night soil” (in other words, human excreta). So they started growing their vegetables hydroponically, using gravel as a growing medium, on Wake Island in the Pacific.
In South Africa, Maxwell Bentley was a pioneer in hydroponics and initiated a system of concrete tanks at the diamond mines along the West Coast to feed the employees. He used vermiculite as a growing medium and wrote a book called “Commercial Hydroponics” about his experiences.
Later, Dudley Harris, who I had the pleasure of meeting, detailed the gravel system that he installed at his home in Camps Bay, Cape Town, in a book which has become a must-have reference book. He used brick and mortar beds as the basis for his system.
The introduction of plastic as a construction material has made the manufacture of hydroponic systems, such as NFT (Nutrient Flow Technique) a great deal easier and lighter, as well as being more accessible to the home grower. This also makes it feasible to have hydroponic installations on the rooftops of city buildings, thus reducing the cost and environmental impacts of transporting produce from rural areas.
A recent article in the Sunday Times features the introduction of a large factory in Japan, where they aim to grow 30,000 heads of lettuce every day, using the most advanced technology and LED lights.
A leading oil company is running a TV advertisement locally, explaining that algae can be used to produce biofuel. Now, algae can be propagated hydroponically, even thriving in brackish or waste water, thus saving precious (and scarce) fresh water, as well as reducing the environmental damage from fossil-based (coal) power stations.
All this goes to show how far we have come since the days of the Babylonians and how you can also take advantage of modern technology to grow your own vegetables and herbs. Just remember, we are only custodians of planet Earth!