THE PAST
Hydroponics, the growing of plants without soil, has developed from the findings
of experiments carried out to determine what substances make plants grow and the
composition of plants. Such work on plant constituents dates back as early as the
1600s. However, plants were being grown in a soilless culture far earlier than this.
Hydroponics is at least as ancient as the pyramids. A primitive form has been
carried on in Kashmir for centuries.
The process of hydroponics growing in our oceans goes back to about the time
the earth was created. Hydroponic growing preceded soil growing. But as a
farming tool, many believe it started in the ancient city of Babylon with it's
famous hanging gardens, which are listed as one of the Seven Wonders of the
Ancient World, and was probably one of the first successful attempts to grow
plants hydroponically.
The floating gardens of the Aztecs of Central America, a nomadic tribe, they
were driven onto the marshy shore of Lake Tenochtitlan, located in the great
central valley of what is now Mexico. Roughly treated by their more powerful
neighbors, denied any arable land, the Aztecs survived by exercising remarkable
powers of invention. Since they had no land on which to grow crops, they
determined to manufacture it from the materials at hand.
In what must have been a long process of trial and error, they learned how to
build rafts of rushes and reeds, lashing the stalks together with tough roots.
Then they dredged up soil from the shallow bottom of the lake, piling it on the
rafts. Because the soil came from the lake bottom, it was rich in a variety of
organic debris, decomposing material that released large amounts of nutrients.
These rafts, called Chinampas, had abundant crops of vegetables, flowers, and
even trees planted on them. The roots of these plants, pushing down towards a
source of water, would grow though the floor of the raft and down into the
water.
These rafts, which never sank, were sometimes joined together to form
floating islands as much as two hundred feet long. Some Chinampas even had a hut
for a resident gardener. On market days, the gardener might pole his raft close
to a market place, picking and handing over vegetables or flowers as shoppers
purchased them.
By force of arms, the Aztecs defeated and conquered the peoples who had once
oppressed them. Despite their great size their empire finally assumed, they
never abandoned the site on the lake. Their once crude village became a huge,
magnificent city and the rafts, invented in a gamble to stave off poverty,
proliferated to keep pace with the demands of the capital city of Central
Mexico.
Upon arriving to the New World in search of gold, the sight of these islands
astonished the conquering Spaniards. Indeed, the spectacle of an entire grove of
trees seemingly suspended on the water must have been perplexing, even
frightening in those 16th century days of the Spanish conquest.
William Prescott, the historian who chronicled the destruction of the Aztec
empire by the Spaniards, described the Chinampas as "Wondering Islands of
Verdure, teeming with flowers and vegetables and moving like rafts over the
water". Chinampas continued in use on the lake well into the nineteenth century,
though in greatly diminished numbers. So, as you can see, hydroponics is not a
new concept.
Many gardening writers have suggested that the Hanging Gardens of Babylon
were in fact an elaborate hydroponic system, into which fresh water rich in
oxygen and nutrients was regularly pumped.
The world's rice crops have been grown in this way from time immemorial. And
also the floating gardens of the Chinese, as described by Marco Polo in his
famous journal, are examples of "hydroponic culture".
Ancient Egyptian hieroglyphic records dating back to several hundred years
B.C. describe the growing of plants in water along the Nile without soil.
Before the time of Aristotle, Theophrastus (327-287 B.C.) undertook various
experiments in crop nutrition. Botanical studies by Dioscorides date back to the
first century A.D.
The earliest recorded scientific approach to discover plant constituents was
in 1600 when Belgian Jan van Helmont showed in his classical experiment that
plants obtain substances from water. He planted a 5-pound willow shoot in a tube
containing 200 pounds of dried soil that was covered to keep out dust. After 5
years of regular watering with rainwater he found the willow shoot increased in
weight by 160 pounds, while the soil lost less than 2 ounces. His conclusion
that plants obtain substances for growth from water was correct. However, he
failed to realize that they also require carbon dioxide and oxygen from the air.
In 1699, John Woodward, a fellow of the Royal Society of England, grew plants
in water containing various types of soil, the first man-made hydroponic
nutrient solution, and found that the greatest growth occurred in water which
contained the most soil. Since they knew little of chemistry in those days, he
was not able to identify specific growing elements. He thereby concluded that
plant growth was a result of certain substances and minerals in the water,
derived from enriched soil, rather than simply from water itself.
In the decades that followed Woodward's research. European plant physiologists
established many things. They proved that water is absorbed by plant roots, that
it passes through the plants stem system, and that it escapes into the air
through pores in the leaves. They showed that plant roots take up minerals from
either soil or water, and that leaves draw carbon dioxide from the air. They
demonstrated that plants roots also take up oxygen.
Further progress in identifying these substances was slow until more
sophisticated research techniques were developed and advances were made.
The modern theory of chemistry, made great advances during the seventeenth
and eighteenth centuries, subsequently revolutionized scientific research.
Plants when analyzed, consisted only of elements derived from water, soil and
air.
The experiments of Sir Humphrey Davy, inventor of the Safety-Lamp, had
evolved a method of effecting chemical decomposition by means of an electric
current. Several of the elements which go to make up matter were brought to
light, and it was now possible for chemists to split-up a compound into it's
constituent parts.
In 1792 the brilliant English scientist Joseph Priestley discovered that
plants placed in a chamber having a high level of "Fixed Air" (Carbon Dioxide)
will gradually absorb the carbon dioxide and give off oxygen. Jean Ingen-Housz,
some two years later, carried Priestley's work one step further, demonstrating
that plants set in a chamber filled with carbon dioxide could replace the gas
with oxygen within several hours if the chamber was placed in sunlight. Because
sunlight alone had no effect on a container of carbon dioxide, it was certain
that the plant was responsible for this remarkable transformation. Ingen-Housz
went on to establish that this process worked more quickly in conditions of
bright light, and that only the green parts of a plant were involved.
In 1804, Nicolas De Saussure proposed and published, results of his
investigations that plants are composed of mineral and chemical elements
obtained from water, soil and air. By 1842 a list of nine elements believed to
be essential to plant growth had been made out. These propositions were later
verified by Jean Baptiste Boussingault (1851), a French scientist who began as a
mineralogist employed by a mining company, turned to agricultural chemistry in
the early 1850s.
In his experiments with inert growing media. By feeding plants with water
solutions of various combinations of soil elements growing in pure sand, quartz
and charcoal (an inert medium not soil), to which were added solutions of known
chemical composition. He concluded that water was essential for plant growth in
providing hydrogen and that plant dry matter consisted of hydrogen plus carbon
and oxygen which came from the air. He also stated that plants contain nitrogen
and other mineral elements, and derive all of their nutrient requirements from
the soil elements he used, he was then able to identify the mineral elements and
what proportions were necessary to optimize plant growth, which was a major
breakthrough.
In 1856 Salm-Horsmar developed techniques using sand and other inert media,
various research workers had demonstrated by that time that plants could be
grown in an inert medium moistened with a water solution containing minerals
required by the plants. The next step was to eliminate the medium entirely and
grow the plants in a water solution containing these minerals.
From discoveries and developments in the years 1859-1865 this technique was
accomplished by two German scientists, Julius von Sachs (1860), professor of
Botany at the University of Wurzburg (1832-1897), and W. Knop (1861), an
agricultural chemist. Knop has been called "The Father of Water Culture".
In that same year (1860), Professor Julius von Sachs published the first
standard formula for a nutrient solution that could be dissolved in water and in
which plants could be successfully grown. This marked the end of the long search
for the source of the nutrients vital to all plants.
This was the origin of "Nutriculture" and similar techniques are still used
today in laboratory studies of plant physiology and plant nutrition. These early
investigations in plant nutrition demonstrated that normal plant growth can be
achieved by immersing the roots of a plant in a water solution containing salts
of nitrogen (N), phosphorus (P), sulfur (S), potassium (K), calcium (Ca), and
magnesium (Mg), which are now defined as the macro elements or macronutrients
(elements required in relatively large amounts).
With further refinements in laboratory techniques and chemistry, scientists
discovered seven elements required by plants in relatively small quantities -
the microelements or trace elements. These include iron (Fe), chlorine (Cl),
manganese (Mn), boron (B), zinc (Zn), copper (Cu), and molybdenum (Mo).
The addition of chemicals to water was found to produce a nutrient solution
which would support plant life, so that by 1920 the laboratory preparation of
water cultures had been standardized and the methods for their use were well
established.
In following years, researchers developed many diverse basic formulas for the
study of plant nutrition. Some of these workers were Tollens (1882), Tottingham
(1914), Shive (1915), Hoagland (1919), Deutschmann (1932), Trelease (1933),
Arnon (1938) and Robbins (1946). Many of their formulas are still used in
laboratory research on plant nutrition and physiology today.
Interest in practical application of this "Nutriculture" did not develop
until about 1925 when the greenhouse industry expressed interest in its use.
Greenhouse soils had to be replaced frequently to overcome problems of soil
structure, fertility and pests. As a result, research workers became aware of
the potential use of nutriculture to replace conventional soil cultural methods.
Prior to 1930, most of the work done with soilless growing was oriented to
the laboratory for various plants experiments. Nutriculture, chemiculture, and
aquiculture were other terms, used during the 1920s and 1930s to describe
soilless culture. Between 1925 and 1935, extensive development took place in
modifying the laboratory techniques of nutriculture to large-scale crop
production.
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,
pumice 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 growing 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 resulting 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. Although 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.
One of the main difficulties with this method was keeping a sufficient supply
of oxygen in the nutrient solution. The plants would exhaust the oxygen rapidly,
taking it up through the roots, and for this reason it was imperative that a
continuous supply of fresh oxygen be introduced into the solution through some
method of aeration. Another problem was supporting the plants so that the
growing tips of the roots were held in the solution properly.
The American Press made their usual, and many irrational claims, hailing it
the discovery of the century, in the most outlandish manner. After an unsettled
period in which unscrupulous promoters tried to cash in on the idea by peddling
useless equipment and materials, more practical research was done and
hydroponics soon became established on a sound scientific basis in horticulture.
With recognition of its two principal advantages, high crop yields and it's
special utility in non-arable regions of the world.
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. Ascension 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 rocky 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 comparable
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 Bahrain 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
been those at isolated bases, notably in Guyana, Iwo Jima and Ascension
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 greenstuffs.
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 minds 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 extremely 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 benefited in many ways. Egg production increased
while cannibalism, a constant problem for poultry men, 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 absolutely 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.
Hydroponics did not reach India until 1946. In the summer of that year the
first research studies were commenced at the Government of Bengal's Experimental
Farm at Kalimpong in the Darjeeling District. At the very beginning a number of
problems peculiar to this sub-continent had to be faced. Even a cursory study of
the various methods which were being practiced in Britain and in America
revealed how unsuited they were for general adoption by the public of India.
Various physiological and practical reasons, in particular the elaborate
expensive apparatus required, were sufficient to prohibit them.
A novel system, of which practicability and simplicity must be the keynotes
would have to be introduced if hydroponics was to succeed in Bengal, or in fact
ever to prove of widespread value to the people of this part of Asia. Careful
appraisal of salient problems during 1946-1947 resulted in the development of
the Bengal System of hydroponics, which represented an effort to meet Indian
requirements.
One object guided all the experiments carried out; to strip hydroponics of
it's complicated devices and to present it to the people of India and the world
as a cheap, easy way of growing vegetables without soil. Now in India, thousands
of householders raise essential vegetables in simple hydroponic units on
rooftops or in backyards, the Bengal System has far more than proved itself, as
being useful in the most adverse conditions.
Numerous letters of appreciation from as far a field as the United Kingdom,
France, the United States, Holland, Israel, Japan, Germany, Algeria, the
Pacific, South and East Africa, Australia, New Zealand, Pakistan, South America,
Burma, the Seychelles, Formosa, and those of the West Indies, have testified to
what a large extent this object has been appreciated by the public, throughout
the world.
Why use hydroponics when we have plenty of land if we would only develop, and
by means of better cultural practices, including manuring, improve it? And then
the cry: But hydroponic yields are after all no better than those which could be
obtained under ideal soil conditions!
Both of these comments call to mind a remark attributed to Charles II (King
Charles II, British monarch (1660-1685)). Emphasizing the difference between
himself and his brother, the Duke of York (afterwards James II), Charles is
reported to have said: "Jamie would if he could, but I could if I would".
Critics of soilless culture fall into these categories. They generally overlook
the fact that to improve the soil of India, or of any other country, so as to
make it perfect, will take 50 to 100 years. Where, after all, can ideal soil
conditions be obtained?
Greenhouse culture, using earth beds, is at the best a worrisome and expensive
affair, involving periodic sterilization and it is only under such conditions,
employing glass, that anything approaching an ideal soil can be produced, even
after a long period of time. And after the first crop begins to mature, alas the
balance is again upset.
An article in Forbes magazine, entitled, "Food Supply - Will Help from
Science Come in Time?" calls hydroponics the "most spectacular current
breakthrough" yet, for solving the world's food problems. An article in the Los
Angeles Times, entitled, "Hydroponics: A New Chapter in Food Technology," states
"...for the past several years, hydroponics has been refined to the point where
it is now a commercially viable way to grow food."
Reading the unresearched accounts in the media, leads on to believe that
hydroponics is a recent development in scientific technology which will save the
world from starvation. Yes, it may very well help save the world from a food
shortage, but it is hardly a new scientific development. In fact, the first
plants on the earth were grown hydroponically. More than half of all plant life
today is growing with hydroponics. And the healthiest, most nutritious plants in
existence are hydroponic plants. I speak of the plants growing in the body of
water, which covers over 70% of the earth's surface - our oceans. There is no
soil in the ocean. Plants draw all their required nutrients directly from the
most complete hydroponic nutrient solution available - sea water.
Among the well-known institutions which have contributed so much to the
establishment of the soilless cultivation of plants as a practical proposition
are, the Universities of Illinois, Ohio, Purdue and California in the United
States; The University of Reading, in Great Britain, famous for it's pioneering
work in new cropping techniques. Canada's Central Experimental Farm at Ottawa,
as well as the internationally famous and important firm of Imperial Chemical
Industries, Ltd., which undertook the adaptation of hydroponics to British
conditions.
Other pioneers of hydroponics were the Boyce Thompson Institute for Plant
Research, New York; the New Jersey Agriculture Experiment Station; the Alabama
Polytechnic Institute; and the Horticultural Experiment Station, Naaldwijk,
Netherlands.
THE PRESENT
With the development of plastics, hydroponics took another large step forward.
If there is one single factor that could be credited with making the hydroponics
industry the success it is today, that factor is plastics.
As mentioned earlier, one of the most pressing problems encountered
everywhere was the constant leaching of detrimental elements into the solution
from concrete, rooting media, and other materials. With the advent of fiberglass
and such plastics as the different types of vinyl, polyethylene film, and the
many kinds of plastic pipe, this problem was virtually eliminated. In the better
producing systems being built in the world today plastics are used throughout,
and other than a few isolated bronze valves, there is absolutely no metal. Even
the pumps are epoxy coated. Using these types of materials, along with an inert
material as a rooting medium, the grower is well on his way to success.
Plastics freed growers from the costly construction associated with the
concrete beds and tanks previously used. Beds are scraped out of the underlying
medium and simply lined with a heavy vinyl (20mil), then filled with the growing
medium. With the development of suitable pumps, time clocks, plastic plumbing,
solenoid valves and other equipment, the entire hydroponic system can now be
automated, or even computerized, reducing both capital and operational costs.
A basic premise to keep in mind about hydroponics is its simplicity. After
the wheel was invented, I am sure many were confused and thought it complicated.
That was because they could not get their minds off all the work the wheel
replaced. This is the way it is with hydroponics. Once you conquer the idea
there must be more to it than this, and forget about the work it eliminates, you
too will agree: It is simple!
Another important breakthrough in hydroponics was the development of a
completely balanced plant food. Work in this area is still continuing, but there
are many ready made formulas available. Most of them are good, but very few, if
any, will work consistently without the use of various additives at different
stages of the crop. There are also many formulas available that can be mixed by
anyone, but the average grower is far better off using one fo the many
commercial formulas.
In addition to the progress rate through the use of plastics and the steady
increase in production because of improved nutrient mixes, another factor of
tremendous importance to the future of the industry was the development of
better hardware for control of the environment in greenhouses.
Initially, nearly all fo the early greenhouses were steam heated, and the
cost of this equipment virtually barred the small grower from entering this
field. With the development of forced-draft heaters that used oil or gas,
however, it became possible to build much smaller units, and the advent of LP
gas, such as butane and propane, made possible the location of greenhouses in
almost any area.
Constant improvements in these heating systems, particularly the introduction
of high-velocity fans and the convection tube method of circulating warm air
throughout a building, gave the grower better temperature control in the
greenhouse. For commercial operations in larger greenhouses, however, a boiler
system using steam or hot water remained the most economical. It gave the grower
wide latitude in the choice of fuels. There has also been continuous
improvements in techniques and equipment for cooling any size greenhouse.
In addition to better environmental control, the use of new materials such as
polyethylene, poly-vinyl films, and translucent fiberglass panels introduced
completely new methods of low cost greenhouse construction. They give the builder
a wide choice of material for covering any size unit and also made possible many
new shapes, sizes, and configurations.
Some of these materials will last only one season; others are guaranteed for
20 years, against clouding, that causes light loss and against shattering from
hail; despite damage to the cover, there was little or no damage to the crop.
Had a light film or glass been used, however, both the crop and cover would have
been completely lost. The films are good for temporary or semi-temporary cover.
Many of these materials also gave light diffusion that is beneficial to most
plants.
The combination of environmental control and improved hydroponic systems has
largely been responsible for the growth of the industry over the past twenty
years, and there can be no question that hydroponics will play a big part in
feeding the world in the future.
As an example of the need for hydroponics, in 1950 there was a total of 3.7
million acres of land under cultivation in the United States. At that time the
population in the United States was 150,718,000. In 1970 the total acreage in
cultivation had dropped to 3.2 million and the population had grown to
204,000,000. In the next 20 years, it is estimated that the population of the
United States will grow to 278,570,000, an increase of 79,000,000 people. It is
hard to project how many more acres will be lost to production during this time.
Above paragraph from United States Department of Agriculture and United States
Department of Commerce.
Hydroponics has become a reality for greenhouse growers in virtually all
climate areas. Large hydroponic installations exist throughout the world for the
growing of both flowers and vegetables. For example, large hydroponic greenhouse
complexes are now in operation in Tucson, Arizona (11 acres); Phoenix, Arizona
(about 15 acres); and Abu Dhabi (over 25 acres), this installation uses desalted
water from the Persian Gulf. Tomatoes and cucumbers have proven to be the most
successful crops. Cabbages, radishes, and snap beans have also done very well.
The Salt River Valley, which surrounds Phoenix, Arizona, illustrates what
happens when the population explodes in an area. The growth pattern of the Salt
River Valley is characteristic of many areas not only in the United States, but
the world over. The first settlers who came into this area were looking for good
land and water, both of which existed in the Salt River Valley. After World War
II, the excellent climate caused a massive population boom.
In 1950, within the boundaries of the Salt River Project, there were 239,802
acres, of which 225,152 acres were assessed as agricultural lands. Between 1950
and 1960, these agricultural lands decreased by 37,795 acres. There was a
further decrease of 35,411 acres between 1960 and 1970. Between 1971 and 1973,
there was an additional loss of 19,172 acres. In 23 years a total of 92,378
acres have been taken out of crop production forever.
The pace at which this fine land is disappearing from production is
constantly accelerating. At the current rate, by 1990 there will be little, if
any, cultivated land left within the present boundaries of the Salt River
Project. Above information supplied by Mr. Reid W. Teeples, Associate General
Manager of Water Resources at the Salt River Project, Phoenix, Arizona.
Traveling over the United States, one can see the same pattern being followed
elsewhere. Another classic example is Southern California, particularly the Los
Angeles area with its tremendous urban sprawl.
With hydroponics, there is no need for soil, and only about one twenty-fifth
as much water is needed as in conventional farming. The hydroponic growers of
the future will be using the roof tops of warehouses and other large buildings
on which to install commercial systems. One such system has been designed by
Deutschmann's Hydroponic Centers of St. Louis, and will be in operation sometime
in 1986. The companies principle crop will be tropical foliage plants, raised in
hydroculture. However, the rooftop greenhouses will be used solely for vegetable
production. The author, who designed this installation, will be their Chief
Olericulturist, and plans to hire all handicapped or underprivileged employees.
Editors Note: The project became a reality in the fall of 1986. By the end of
the summer of 1988, a total of 7 rooftop greenhouses were in full production in
the St. Louis area. The companies hydrocultural sales of tropical foliage plants
had far surpassed their expectations with 433 ten inch hydroculture foliage
plants being sold daily through 1994. The vegetable production department,
utilizing the rooftop greenhouses, was thriving equally as well when an
unfortunate event, unrelated to the business, forced the company to temporarily
suspend operations. The patented hydrocultural planting system developed by the
author is still available today through various companies and dealers who have
maintained stock and new production facilities are operated by EcoTek
Hydrocultural Plant Systems, Inc. of St. Louis.
There is ample space on almost any flat rooftop. All that is needed in
addition to this space is electricity, fuel and water. Systems built in this
manner will have the added advantage of being at, or near, the marketplace,
eliminating the need for long-distance transportation of produce, such as we
have today. Because the environment within the hydroponic installations can be
controlled, these systems can produce vegetables year round in almost any
climate.
The system designed and built in St. Louis proves there is no question that
we already have the technology to build such systems, inexpensively. There will,
however, be other systems, built by or for the homeowner that will take up very
little space. Some of these will be small enough to be installed in the kitchen
or other parts of the home. They will produce an abundant supply of many types
of food, particularly lettuce, strawberries, and similar crops. There are
already workable units of this type available now.
Today, hydroponics is an established branch of agronomical science, it helps
feed millions of people; these units may be found flourishing in the deserts of
Israel, Lebanon and Kuwait, on the islands of Ceylon, the Phillipines, on the
rooftops of Calcutta and in the parched villages of West Bengal.
In the Canary Islands, hundreds of acres of land are covered with
polyethylene supported by posts to form a single continuous structure housing
tomatoes grown hydroponically. The structure has open walls so that the
prevailing wind blows through to cool the plants. The structure helps to reduce
transpiration loss of water from the plants and to protect them from sudden
rainstorms. Such structures can also be used in such areas as the Caribbean and
Hawaii.
Almost every state in the United States has a substantial hydroponic
greenhouse industry. Canada also uses hydroponics extensively in the growing of
greenhouse vegetable crops. About 90% of the greenhouse industry in British
Columbia, Canada, uses sawdust culture to overcome soil structures and soil pest
problems.
One-half of Vancouver Island's tomato crop and one-fifth of Moscow's are
hydroponically produced. There are full-fledged hydroponic systems in American
Nuclear Submarines, Russian Space Stations and on off-shore drilling rigs. Large
zoos keep their animals healthy with hydroponic green food, and race horses stay
sleek and powerful on grass grown hydroponically year round.
There are large and small systems used by companies and individuals as far
north as Baffin Island and Eskimo Point in Canada's Arctic. Commercial growers
are using this marvelous technique to produce food on a large scale from Israel
to India, and from Armenia to the Sahara.
In arid regions of the world, such as Mexico and the Middle East, where the
supply of fresh water is limited, hydroponic complexes combined with
desalination units are being developed to use sea water as a source of fresh
water. The complexes are located near the ocean and the plants are grown in the
existing beach sand. In other areas of the world, such as the Middle East, there
is little land suitable for farming. Because of the development of the oil
industry and the subsequent flow of wealth, the building of large hydroponic
farms to feed the exploding populations in these nations is inevitable. If there
is any one industry in the world today who's time has come, it is hydroponics.
WHY GROW FOOD?
Food is something most Americans take for granted. Yet, according to a recent poll
"Gardens for All," by the Gallup Organization, 34 million households in America
(that's over 43%) grow food, and the number is increasing rapidly. Not since the old
Victory Garden era has there been more interest in gardening for food.
Years ago, most people were interested in gardening as a hobby. Few were
concerned with taste or nutrition, and fewer still were interested in grocery
costs or self-sufficiency. As long as good quality vegetables could be purchased
at reasonable prices, there was little concern.
In the past several years, interests have changed. Fewer gardeners are
hobbyists. Many are interested in food costs, and more still are concerned about
taste and the nutritional values of the vegetables they feed their families, the
effects of chemicals, both to the environment and health-wise. Also, there are
growing numbers of people in the United States who have a strong desire to
become more self-sustaining.
Countries like the Canary Islands balance their economies by exporting vast
amounts of soilless-produced tomatoes, cucumbers and salad greens to industrial
states like Britain every year. From the Caribbean area, too, Puerto Rican and
Mexican growers ship immense quantities of luscious hydroponic fruits and
greenstuffs to the insatiable United States and Canadian markets. In England,
Germany, France, the Netherlands and Switzerland, flower firms often prefer to
employ the soilless method for commercial purposes, especially for the
production of carnations and other quality blooms. Roses and chrysanthemums are
grown extensively in Colorado and neighboring states for export. In 1971
nurseries in those areas made gross profits of over 25 million dollars from
hydroponically raised flowers alone.
In the year 1975 alone, four different commercial Hawaiian growers were
producing tomatoes hydroponically and more installations were planned.
Stateside, more than five hundred commercial hydroponic greenhouses were in
operation in the United States.
For one reason or another, most American greenhouse growers will not admit
that they are using hydroponics to raise most, if not all of their flowers and
plants. I believe one reason for this is because they use a method that so
closely resembles the Bengal System, and do all of their fertilizing and
watering by hand, that they are to embarrassed to refer to what they do as a form
of hydroponics. Editors Note: In the United States the proven Bengel System is
referred to as the modified slop method of hydroponics!
The authorities in the U.S.S.R. have encouraged the extension of hydroponics
in their country. Large hothouses, soilless farms and gardens exist at Moscow
and Kiev, while in Armenia an Institute of Hydroponics has been established at
Erevan in the Caucasus region.
Officially, soilless cultivation of plants is looked upon in Russia as a
biological industry coming between horticulture and manufacturing. Other
countries, not already mentioned, where hydroponics is in current use include
Australia, New Zealand, Spain, South Africa, Israel, particularly in the Negev
Desert and along the Dead Sea, Italy, the Scandinavian lands, the Bahama
Islands, Central Africa, East Africa, Kuwait, Brazil, Poland, the Seychells,
Singapore, Malaysia and Iran. This list is not, of course, by any means
exhaustive, but it does give some idea of how widely spread soilless gardening
is today.
According to Funk & Wagnall's New Comprehensive International Dictionary:
"hy-dro-pon-ics...n. pl. (construed as singular) soilless agriculture; the
raising of plants in nutrient/mineral solutions without earth around the
roots;..."
That's easy enough - growing without soil. I remember when I first learned
about vegetable gardening; it seemed as though everything related to the soil -
most of the work and most of the knowledge of farming. The soil had to have the
proper texture, structure, and porosity. It had to include all the nutrients
required for growing. Even after the garden was planted, the soil had to be
worked and reworked.
If I could have eliminated the soil, what a pleasure it would have been to
grow my own food. Without soil, more time could have been devoted to more
productive efforts, such as maximizing my yields by proper pruning, pollination,
intercropping, and proper harvesting. But now I use no soil. I grow with
hydroponics.
FOOD TRENDS IN AMERICA
Everyday in America, there are 5,000 more people to feed from the production
of farmland which is shrinking by over 15,000 acres a day. That is a loss of
almost 6 million acres each year, 3 million to erosion and just poor land
management, and 3 million to progress in the form of more homes, factories, and roads.
If we continue at this rate, I feel the demand for food may some day pass our
ability to supply it as abundantly as we have in the past. In all probability,
we will have to watch or diets a little more carefully and learn how to stop
wasting food, as we had to learn how to stop wasting energy.
I do not mean to alarm anyone. Barring a catastrophe, I am convinced there
will always be adequate supplies of food. No one will starve in America. But
what will happen to our once high standards for taste and nutrition? And how
much will food cost, when compared to our monthly incomes?
Not many years ago, most of our fresh food and much of our processed food was
produced within a 100 mile radius of our homes. There were hundreds of local
farmers and food processors, each competing for our business. With an abundance
of food available, we could afford to be choosy. If we did not like what we were
offered, we could voice a complaint or just buy from another source.
In those days "fresh" meant fresh. Local farmers were not as skilled in the
techniques of disguising poor quality. Since good fresh produce was available at
reasonable prices, we would not think of eating a meal without several servings
of fresh vegetables, not frozen or canned, but fresh.
We see a much different picture today. Local farmers are almost extinct. We
now have larger and more centralized farms, larger food processors and larger
chemical companies supplying or farmers and food processors. It is estimated, by
the year 2000, one percent of our farms will control over half our food
supplies. Also, over 60 percent of farm profits will go to as few as 50 major
companies.
We cannot ignore the worldwide food shortage any longer. We need more food
from fewer acres. But in order to get more from less, sacrifices will have to be
made. Among these sacrifices will be "fresh" food which is not really fresh,
less control over food quality, higher food prices, and a much higher ration of
processed food over fresh food.
With the demise of our local farmers, I believe we have already lost out on
fresh food and local control. Now in order to keep food costs from getting out
of control, it only stands to reason more food will have to come to us
processed.
It is estimated that 20 percent of all food produced in America (about 137
million tons, worth $31 billon) is wasted. Of that, about 60 million tons, worth
$5 billion is simply left in fields and orchards for lack of commercial value.
Add to that the increasingly high costs of packaging, storing, preserving,
handling, and transportation after it leaves the field, and the result is clear.
We as a nation must convert more of our crop yields from fresh produce to
processed foods.
True hydroponic culture is generally a means of growing plants in a nutrient
solution using no soil or other rooting medium, although today almost all of the
many different methods of growing plants without soil employ various types of
inert material for a rooting medium, such as gravel, haydite, perlite,
vermiculite, pumice, sand and others.
What is known as the Herbagere method hydroponic cultivation, invented by a
Belgian Botanist named Gaston Perin, is beginning to find widespread use in the
United States. this growing technique utilizes a number of shallow rectangular
trays containing germinating seeds. The trays are stacked one above the other
in a sealed growing chamber. Each of the tray bottoms contains narrow slits.
This feature permits nutrient solution introduced at the top tray to drip down
through each tray in the stack. This technique is sometimes referred to as
vertical farming. It has been applied to the growing of highly nutritious grass
for feeding of livestock and zoo animals.
The San Diego Zoo is one of a number of zoos that operate a hydroponic
growing chamber of this type. It's the size of a large house trailer. Within the
chamber a total of 252 white plastic trays are arranged in several neat tiers.
Each day, 36 trays, one seventh of the total, are seeded with presoaked
barley. Nutrient solution is sprayed over the trays several times each day to
keep the seeds moist. The temperature in the chamber is kept at from 64 to 68
degrees and the trays are bathed in fluorescent light continuously, which serve
to stimulate seed growth.
Since the growing cycle is seven days long, each day mature barley is
harvested from another set of thirty-six trays. The barley daily harvest yields
from five hundred to six hundred pounds of grass and roots. Zoos in New York
City (the Bronx Zoo), Chicago, Phoenix and St. Louis operate the same kind of
growing chambers. At the Bronx Zoo, the grass is fed to most of the hoofed
stock; the zebras, antelope, deer and Mongolian wild horses.
Editors Note: The St. Louis Zoo directors decided to reutilized their
Herbagere climate controlled building for the rearing of rare baby birds, due to
lack of funds to procure proper facilities for these animals. Their feed costs
increased and animal health went down proportionately. The rearing of the rare
baby birds was unsuccessful and all succumbed!
Lettuce is another crop that lends itself to vertical farming. Lettuce
seedlings in small planting boxes are placed in trays which are stacked one
above the other in a metal rack. After their diet of liquid nutrients for one
month the plants reach maturity.
In the case of tomatoes, the dirt farmer raises about 3,500 plants per acre.
In hydroponics, the plants can be placed much closer together, it's possible to
cultivate as many as 10,000 plants on an acre of land.
In normal farming, crops have to be rotated, that is, grown in a fixed order
of succession. Otherwise, the nutrient level of the soil falls below established
minimums. Plainly speaking, the soil "Wears Out." With soilless culture, there's
never any need to rotate crops. The farmer checks the solution and adds whatever
nutrients may be needed. Thus the nutrient level can be just as high at harvest
time as it was the day the crop was planted, and the same type of crop can be
grown in endless succession. If however, the grower decides he wants to change
to a different crop after the harvest, it's a simple matter to do so. Another
plus is growing does not have to be done on a seasonal basis. Crops can be
started so that a continuous supply of most any vegetable or fruit can be
obtained at any time of the year.
THE FUTURE
Hydroponics is a very young science. It has been used on a commercial basis for
only 40 years. However, even in this relatively short period of time, it has been
adapted to many situations, from outdoor field culture and indoor greenhouse
culture to highly specialized culture in atomic submarines to grow fresh vegetable
for crews. It is a space age science, but at the same time can be used in developing
countries of the Third World to provide intensive food production in a limited area.
It's only restraints are sources of fresh water and nutrients. In areas where fresh
water is not available, hydroponics can use seawater through desalination. Therefore,
it has potential application in providing food in areas having vast regions of
non-arable land, such as deserts. Hydroponic complexes can be located along
coastal regions in combination with petroleum-fueled or atomic desalination
units, using the beach sand as the medium for growing the plants.
Another area in which hydroponics promises to play an important role in the
future is growing seedlings for reforestation, orchards, and ornamental
shrubbery. In a report published in 1966, researchers at the University of
Wisconsin stated that seedlings of white cedar, blue and white spruce, red pine,
and others were grown in a controlled environment. Using a hydroponic system
with controlled feedings of a nutrient solution, the results of growth in one
year were three to four times as great as in year old nursery grown seedlings.
The extension of the growing season in this northern area, through the use of
hydroponics and more concentrated use of space, made it possible to grow five to
ten times a many plants in a given area. Some plantings of pine were 18 years old
at the time this report was published and were said to be growing vigorously.
Report - American Nursery Man, 1966.
Hydroponics is a valuable means of growing fresh vegetables not only in
countries having little arable land and in those which are very small in area
yet have a large population. It could be particularly useful in some smaller
countries whose chief industry is tourism. In such countries, tourist
facilities, such as hotels, have often taken over most arable areas of the
country, forcing local agriculture out of existence. Hydroponics could be used
on the remaining non-arable land to provide sufficient fresh vegetables for the
indigenous population as well as the tourists. Typical examples of such regions
are the West Indies and Hawaii, which have a large tourist industry and very
little farm land in vegetable production.
To illustrate the potential use of hydroponics, tomatoes grown in this way
could yield 150 tons per acre annually. A 10-acre site could produce 3 million
pounds annually. In Canada, the average per capita consumption of tomatoes is 20
pounds. Thus, with a population of 20 million, the total annual consumption of
tomatoes is 400 million pounds (200,000 tons). These tomatoes could be produced
hydroponically on 1,300 acres of land!
But there continues to be problems that hamper the growth and development of
hydroponics as a whole. One problem is the negative attitude of the directors
and people of position in many of our colleges, universities and government
agencies, which has ranged from complete disinterest, to open hostility. This
attitude partly results from their own failure to achieve crop yields matching
those of many hydroponic growers.
Fortunately, in some of our schools, there are people who not only have open
minds, but who have also given generously of their time and talents to help
growers establish very successful hydroponic farms.
Another problem that has developed in the past few years is the
ever-increasing cost of energy for heating. In many areas the high cost of fuel
has caused a number of installations that were operating at a profit to suddenly
plunge deeply into the red, and some operators have been forced to shut down
entirely in the colder months. Since this is the time of year when vegetables
are at or near peak prices, these increased fuel costs have had a disastrous
effect on the industry as a whole, including soil-based greenhouse men.
One bright spot in this picture is the development of solar heating systems.
Much research has and is being done in this field, and there are many
ready-built systems available on the market today. Also available are a number
of publications with detailed plans on how to build one's own solar energy
system. There will of course, be many new developments in this field over the
next few years, and solar energy may eventually solve the dilemma for all
growers.
Currently, plans are being drawn for using the techniques of soilless culture
on space flights and even on the moon, or beyond. For hydroponics, the future
seems very bright.
The biggest danger to the growth and development of hydroponics has been the
influx of "instant experts" over the past 10 years. The success of many growers
using properly designed equipment has attracted these self-styled authorities in
ever-growing numbers. Making extravagant claims, they have sold many shabby,
poorly made copies of workable units with the assurance that this was the easy
road to riches. Many of these fly-by-night promotions have been short lived,
but, sadly, others continue to flourish.
The cost to the would-be commercial grower for a properly designed hydroponic
system, housed in a manner that provides good environmental control, can run
into thousands of dollars. For this reason, he should check very closely the
qualifications of the seller. He should require proof of claims regarding
production and profit capability, back-up service after the sale, research
facilities and past records of the manufacturing company.
If a person is willing to work and apply himself, plants can be grown
hydroponically by a complete novice with no past experience at growing crops.
The owner of a small 10x12 foot hydroponic greenhouse will be able to produce
all the fresh vegetables needed by a family of four or five, provided he
operates the unit on a year round basis.
Hydroponics can also be profitable on a commercial scale if the grower
devotes the time and attention required for any successful business. The average
yield of tomatoes per acre is eighteen times greater than in conventional soil
methods. Rarely do pesticides have to be used.
Hydroponics is a fascinating method of growing plants and can give the
hobbyist or serious grower many hours of pleasure.
Gary Deutschmann.