Hydroponics in Commercial Food Production

Commercial Hydroponics

With the first successful application of hydroponics techniques in the 1930s the stage was set for a paradigm shift in crop production from conventional geoponics or cultivation in soil to hydroponics or soil less cultivation. The first crops to be commercially harvested with hydroponics included tomatoes and peppers, but the techniques were soon successfully extended to other crops such as lettuce, cucumbers and others. It was not long before hydroponics techniques were successfully adapted even to cut flowers production; in fact any plant can today be grown hyrdroponically.


Commercial Systems Overview

Commercial hydroponics systems can be classified into bare root systems comprising nutrient film technique (NFT), deep flow and aeroponics systems and substrate systems.
Bare root systems do not use media to anchor the plant roots; the roots are left bare while in substrate systems plant roots are anchored in media such as perlite, vermiculite, sawdust, peat etc. Hydroponics is basically all about growing plants in a controlled environment and this is best provided outdoors in greenhouses that can incorporate several means to monitor, regulate and control the environment inside them. For instance, the air entering the greenhouse can be filtered to exclude entry to pests and parasites that can harm plant growth. Such means help provide optimal conditions for plant growth both in and out of season. In fact, hydroponics allows cultivation throughout the year which makes for year round availability of hydroponically grown produce at all major supermarkets across North America. Valued at 2.4 billion dollars the hydroponic greenhouse vegetable industry has a growth rate of 10 percent per year and accounts for nearly 95 percent of the greenhouse vegetables produced in North America.


Hydroponics Advantages

The extension of the growing season is not the only advantage contributing to the growing popularity of hydroponics production with both growers and consumers. There are several additional advantages as well including nutritious, healthy and clean produce, improved and consistent vegetable quality and elimination of the use of pesticides and herbicides. Pesticides and other chemicals used in conventional agriculture have an adverse environmental impact; the run off from these chemicals contaminate groundwater supplies. Commercial hydroponics systems eliminate these toxic chemicals and contribute substantially to keeping the groundwater free from contamination.


Yields

Commercial hydroponics systems have proved more productive than conventional systems of agriculture not only in the laboratory but even in actual practice. Most commercial hydroponics greenhouse facilities are built large to take advantage of economies of scale; typically these cover areas more than 10 acres while smaller ones measure around two acres. In the research greenhouse, yields with hydroponics techniques have averaged around 20 to 25% higher than in conventional soil cultivation. In actual commercial practice, however, over a number of years, the yield of hydroponically grown tomatoes can be more than double that of soil based systems due to the reduced turnover time between crops, better nutrition and crop management. Additionally commercial hydroponics growing techniques are also less demanding of chemicals for root zone sterilization and control of pests, weeds etc.


The dramatic increase in yields with hydroponics is best illustrated if we consider the actual production figures of soil grown and hydroponically grown produce. Field grown tomatoes average yields ranging between 40,000 to 60, 000 pounds per acre; on the other hand top growing hydroponics facilities in the US and Canada report average yields of more than 650,000 pounds of tomatoes per acre. Additionally, given the fact that only 10 years ago top hydroponics producers were producing around 400,000 pounds per acre, the increase in yields with improvements in growing practices has been truly phenomenal. Similar production figures can be quoted for other agricultural produce like cucumbers with 10,000 pounds per acre for field production and 200,000 per acre for hydroponic greenhouse yields. Hydroponics lettuce and pepper yields too average around four times the corresponding yields of agricultural production.


Global Trends

Given the number of advantages of hydroponics it is not surprising that hydroponics techniques are increasingly finding favor for commercial food production in many countries all over the world. According to recent estimates countries having substantial commercial hydroponics production include Israel – 30,000 acres, Holland 10,000 acres, England 4,200 acres and Australia and New Zealand around 8,000 acres between them. The fastest growing area for commercial vegetable greenhouses is Mexico. There are several reasons for this including free trade and favorable winter conditions that attract vegetable growers in large numbers. Mexico has summers that are considered hot in the summer, but with greenhouses located at the right altitudes vegetables can be grown in the hot summers as well as the cold winters. Though much of the produce comes from low tech plastic houses, many of these greenhouses use hydroponics technology, which indicates the growing popularity of hydroponics in commercial food production.

Indoor Hydroponics Systems

Though plants have been traditionally grown outdoors in soil, with the use of hydroponics techniques, it is possible to grow plants indoors, in fact in any place.
Hydroponics techniques have been successfully used to cultivate a wide variety of plants even in places with climates that do not support plant growth like deserts and Polar Regions.


Controlled Environment

Growing plants indoors with hydroponics is basically all about simulating the natural growth environment indoors, usually in specially designed grow rooms or grow chambers. The plants can then be supplied with the essential growth inputs in a controlled manner to stimulate and regulate growth. Hydroponics often gives results far superior to conventional cultivation due the fact that it offers a measure of control over factors like nutrition, lighting etc.


Unlike conventional cultivation, hydroponics cultivation does not use soil, instead it uses other grow media to serve the same purpose. The material may be water, gravel, sand or vermiculite; even bran and coconut fiber can be used. The medium serves to hold the plant and also facilitates the supply of nutrients in the form of a solution. The solution is then added to the grow media; the plant roots are thus bathed in a solution which is rich in nutrients like phosphorus, nitrogen, potassium and trace minerals. Additionally, since the medium is highly porous, it is ideally suited to ensure the supply of oxygen to the roots.


Energy Requirements

Plants make their own food and for this they need energy, which they get from the sun’s radiation. Instead of sunlight, indoor hydroponics systems make use of the radiation from grow lights that are artificial light sources. These can be incorporated in the grow chamber and controlled with suitable control systems to provide the type and pattern of lighting in line with the plant’s requirements. The energy requirements of plants are not constant; they differ at different points of the plant growth cycle. Artificial lighting and control systems offer optimal usage of energy which enhances growth to the plant’s full potential.


Hydroponics Techniques

Plants also need air and carbon dioxide and these are supplied in various ways using oscillating, fans, pumps, cylinders etc. With the basic systems in place the indoor grow room provides all the essential growth factors needed to support plant growth. There are several systems that are all essentially based on the same basic considerations but differ in some respects of detail. In some systems, the plant roots are constantly in contact with the nutrient solution while in other systems the solution is supplied and drained at intervals. In some systems the roots are not bathed in solution, but are held exposed to air and the nutrient solution is misted around them. In some systems growing trays are used to support plants while in others the plants are supported in tubes.


Four Season Crops

Hydroponics systems can be built using commercially available components or they can be built using available material; they can also be obtained as kits from the market. With several options now available to him, the gardening enthusiast can put his ingenuity and imagination to good use for growing plants all the year round rain, hail or snow.