In the late 1920s and early 1930s, Dr. William F. Gericke of the University of California extended his laboratory experiments and work on plant nutrition to practical crops growing outside for large scale commercial applications. In doing so he termed these nutriculture systems "hydroponics". The word was derived from two Greek words, hydro, meaning water and ponos meaning labor - literally "water-working". His work is considered the basis for all forms of hydroponic growing, even though it was primarily limited to the water culture without the use of any rooting medium.
Hydroponics is now defined as the science of growing plants without the use of soil, but by use of an inert medium, such as gravel, sand, peat, vermiculite, pubice or sawdust, to which is added a nutrient solution containing all the essential elements needed by the plant for its normal growth and development. Since many hydroponic methods employ some type of medium that contains organic material like peat or sawdust, it is often termed "soilless culture", while water culture alone would be true hydroponics.
Today, hydroponics is the term used to describe the several ways in which plants can be raised without soil. These methods, also known generally as soilless gardening, include raising plants in containers filled with water and any one of a number of non-soil mediums - including gravel, sand, vermiculite and other more exotic mediums, such as crushed rocks or bricks, shards of cinder blocks, and even styrofoam.
There are several excellent reasons for replacing soil with a sterile medium. Soil-borne pests and diseases are immediately eliminated, as are weeds. And the labor involved in tending your plants is markedly reduced.
More important, raising plants in a non-soil medium will allow you to grow more plants in a limited amount of space. Food crops will mature more rapidly and produce greater yields. Water and fertilizer are conserved, since they can be reused. In addition, hydroponics allows you to exert greater control over your plants, to unsure more uniform results.
All of this is made possible by the relationship of a plant with its growing medium. It isn`t soil that plants need - it`s the reserves of nutrients and moisture contained in the soil, as well as the support the soil renders the plant. Any growing medium will give adequate support. And by raising plants in a sterile grwoing medium in which there are no reserves of nutrients, you can be sure that every plant gets the precise amount of water and nutrients it needs. Soil often tends to leach water and nutrients away from plants, making the application of correct amounts of fertilizer very difficult. In hydroponics, the necessary nutrients are dissolved in water, and this rululting solution is applied to the plants in exact doses at prescribed intervals.
Until 1936, raising plants in a water and nutrient solution was a practice restricted to laboratories, where it was used to facilitate the study of plant growth and root development.
Dr. Gericke grew vegetables hydroponically, including root crops, such as beets, radishes, carrots, potatoes, and cereal crops, fruits, ornamentals and flowers. Using water culture in large tanks in his laboratory at the University of California, he succeeded in growing tomatoes to heights of 25 feet.
Photographs of the professor standing on a step ladder to gather in his crop appeared in newspapers throughout the country. Allthough spectacular, his system was a little premature for commercial applications. It was far too sensitive and required constant technical monitoring.
Many would-be hydroponic growers encountered problems with the Gericke system because it required a great deal of technical knowledge and ingenuity to build. Gericke`s system consisted of a series of troughs or basins over which he stretched a fine wire mesh. This in turn was covered by a mulch of straw or other material. The plants were placed on this mesh, with the roots extending downward into a water/nutrient solution in the basin.
In 1936, W. F. Gericke and J. R. Travernetti of the University of California published an account of the successful cultivation of tomatoes in a water and nutrient solution. Since then a number of commercial growers started experimenting with the techniques, and researchers and agronomists at a number of agricultural colleges began working to simplify and perfect the procedures. Numerous hydroponic units, some on a very large scale, have been built in Mexico, Puerto Rico, Hawaii, Israel, Japan, India, and Europe. In the United States, without much public awareness, hydroponics has become big business, more than 500 hydroponic greenhouses have been started.
Dr. Gericke`s application of hydroponics soon proved itself by providing food for troops stationed on non-arable islands in the Pacific in the early 1940s.
The first triumph came when Pan American Airways decided to establish a hydroponicum on the distant and barren Wake Island in the middle of the Pacific Ocean in order to provide the passengers and crews of the airlines with regular supplies of fresh vegetables. Then the British Ministry of Agriculture began to take an active interest in hydroponics, especially since its potential importance in the Grow-More-Food Campaign during the 1939-1945 war was fully realized.
During the late 1940s, Robert B. and Alice P. Withrow, working at Purdue University, developed a more practical hydroponic method. They used inert gravel as a rooting medium. By alternately flooding and draining the gravel in a container, plants were given maximum amounts of both nutrient solution and air to the roots. This method later became known as the gravel method of hydroponics, sometimes also termed nutriculture.
In wartime the shipping of fresh vegetables to overseas outposts was not practical, and a coral island is not a place to grow them, hydroponics solved the problem. During World War II, hydroponics, using the gravel method, was given its first real test as a viable source for fresh vegetables by the U. S. Armed Forces.
In 1945 the U. S. Air Force solved it`s problem of providing it`s personnel with fresh vegetables by practicing hydroponics on a large scale giving new impetus to the culture.
One of the first of several large hydroponics farms was built on Ascension Island in the South Atlantic. Ascention was used as a rest and fuel stop by the United States Air Force, and the island was completely barren. Since it was necessary to keep a large force there to service planes, all food had to be flown or shipped in. There was a critical need for fresh vegetables, and for this reason the first of many such hydroponic installations established by our armed forces was built there. The plants were grown in a gravel medium with the solution pumped into the gravel on a preset cycle. The techniques developed on Ascension were used in later installations on various islands in the Pacific such as Iwo Jima and Okinawa.
On Wake Island, an atoll in the Pacific Ocean west of Hawaii, normally incapable of producing crops, the rocy nature of the terrain ruled out conventional farming. The U. S. Air Force constructed small hydroponic growing beds there that provided only 120 square feet of growing area. However, once the operation become productive, it`s weekly yield consisted of 30 pounds of tomatoes, 20 pounds of string beans, 40 pounds of sweet corn and 20 heads of lettuce.
The U. S. Army also established hydroponic growing beds on the island of Iwo Jima that employed crushed volcanic rock as the growing medium, with comperable yields.
During this same period (1945), the Air Ministry in London took steps to commence soilless culture at the desert base of Habbaniya in Iraq, and at the arid island of Bahrein in the Persian Gulf, where important oil fields are situated. In the case of the Habbaniya, a vital link in Allied communications, all vegetables had had to be brought by air from Palestine to feed the troops stationed there, and expensive business.
Both the American Army and the Royal Air Force opened hydroponic units at military bases. Many millions of tons of vegetables produced without soil were eaten by Allied Soldiers and Airmen during the war years. After World War II the military command continued to use hydroponics. For example, The United States Army has a special hydroponics branch, which grew over 8,000,000 lbs. of fresh produce during 1952, a peak year for military demand.
They also established on of the worlds largest hydroponic installations, a 22 hectare project at Chofu, Japan. It became necessary to use hydroponics in Japan because of the method of fertilization of the soil by the Japanese.
It had been their practice for many years to use "Night Soil", containing human excreta as a fertilizer. The soil was highly contaminated with various types of bacteria and amoeba, and although the Japanese were immune to these organisms, the occupying troops were not.
Covering 55 acres, it was designed to produce both seedlings and mature vegetables for American occupation forces. It remained in operation for over 15 years. The largest hydroponic installations up to that time were built in Japan using the gravel culture method. Some of the most successful installations have beeen those at isolated bases, noteably in Guyana, Iwo Jima and Ascention Island.
After World War II, a number of commercial installations were built in the United States. The majority of these were located in Florida. Most were out of doors and subject to the rigors of the weather. Poor construction techniques and operating practices caused many of them to be unsuccessful and production inconsistent. However, the commercial use of hydroponics, grew and expanded throughout the world in the 1950s to such countries as Italy, Spain, France, England, Germany, Sweden, the USSR and Israel.
One of the many problems encountered by the early hydroponics pioneers was caused by the concrete used for the growing beds. Lime and other elements leached into the nutrient solution. In addition, most metal was also affected by the various elements in the solution. In many of these early gardens, galvanized and iron pipe were used. Not only did they corrode very quickly, but elements harmful or toxic to the plants were released into the nutrient solution.
Nevertheless, interest in hydroponic culture continued for several reasons. First, no soil was needed, and large plant population could be grown in a very small area. Second, when fed properly, optimum production could be attained. With most vegetables, growth was accelerated and, as a rule, the quality was better than that of soil grown vegetables. Produce grown hydroponically had much longer shelf life or keeping qualities.
Many of the oil and mining companies built large gardens at some of their installations in different parts of the world where conventional farming methods were not feasible. Some were in desert areas with little or no rainfall or subsurface waters, and others were on islands, such as those in the Caribbean, with little or no soil suitable for vegetable production.
Big commercial American headquarters in the Far East have over 80 acres devoted to vegetable units, to feed landless city dwellers, while various oil companies in the West Indies, the Middle East, the sandy wastes of the Arabian Peninsula and the Sahara Desert, operating in barren areas, especially off the Venezuelan Coast at Aruba and Curacao, and in Kuwait have found soilless methods invaluable for ensuring that their employees get a regular ration of clean, health-giving greenstuff.
In the United States, extensive commercial hydroponics exist, producing great quantities of food daily, especially in Illinois, Ohio, California, Arizona, Indiana, Missouri and Florida, and there has been a noteworthy development of soilless culture in Mexico and neighboring areas of Central America.
In addition to the large commercial systems built between 1945 and the 1960s, much work was done on small units for apartments, homes, and back yards, for growing both flowers and vegetables. Many of these were not a complete success because of a number of factors: Poor rooting media, the use of unsuitable materials, particularly in constructing the troughs used as growing beds, and crude environmental control.
Even with the lack of success in many of these ventures, however, hydroponic growers the world over were convinced that their problems could be solved. There was also a growing conviction in the nimds of many that the perfection of this method of growing food was absolutely essential in light of declining food production and the worldwide population explosion.
Recent surveys have indicated that there are over 1,000,000 household soilless culture units operating in the United States for the production of food alone. Russia, France, Canada, South Africa, Holland, Japan, Australia and Germany are among other countries where hydroponics is receiving the attention it deserves.
In addition to the work being done to develop hydroponic systems for the production of vegetables, however, between 1930 and 1960 similar work was being conducted to develop a system to produce livestock and poultry feed. Researchers had found that cereal grains could be grown very rapidly in this manner. Using grains such as barley, they proved that 5 pounds of seed could be converted into 35 pounds of lush green feed in 7 days. When used as a supplement to normal rations, this green feed was extreemely beneficial for all types of animals and birds. In lactating animals, milk flow was increased. In the feed lots, better conversion rates and gains were achieved at less cost per pound of grain. In breeding stock the potency of males and conception in females increased dramatically. Poultry also benefitted in many ways. Egg production increased while cannibalism, a constant problem for poultrymen, ceased.
Here again, however, in developing a system that would produce consistently, a number of problems arose. The early systems had little or no environmental control, and with no control of temperature or humidity, there was a constant fluctuation in the growth rate. Mold and fungi in the grasses were an ever-present problem. The use of thoroughly clean seed grain with a high germination ratio was found to be absolutley essential if a good growth rate was to be achieved.
Nevertheless, in the face of these and other obstacles, a few dedicated researchers continued to work to perfect a system that could produce this nutritious feed continuously. With the development of new techniques, equipment, and materials, units became available that were virtually trouble free. Many of these are in use today on ranches, farms, and in zoos all over the world.