Science and technology are moving forward: scientists worldwide are working to make the production of fresh and healthy food accessible, cost-effective, and sustainable. So, the classic beds and greenhouses are being replaced by hydroponics – growing plants without soil in nutrient solutions.
Hydroponics provides the basis for obtaining higher yields from cultivated plants than conventional growing methods. Today you will find hydroponically grown herbs, berries, and vegetables in any medium or large supermarket. But on the product’s label, you are unlikely to find the inscription “hydroponic.”
There are several reasons for this: hydroponics is a relatively young field of agriculture, which is quite high-tech, which creates the prerequisites for the uninformed to interpret it as “chemistry.” Well, chemically engineered foods still bear the stigma of “unhealthy.” So to dispel all the doubts, the article is here for you to inform all about hydroponics.
Table of Contents
Hydroponics and its History
Hydroponics is a recent technique of growing plants in special solutions. Translated from Greek, the term hydroponics means “working solution.” With this method, plants without soil are in the substrate, which supports the root system and receives the necessary nutrients from the solution. It is selected individually for each plant, depending on the species.
The soilless method of growing plants began to be used in ancient times. The Hanging Gardens in Babylon are the first successful attempt at hydroponics. In the Floating Gardens of the Aztecs, located in Central America, they applied the same technology.
When warlike neighbors drove out the nomadic Indians living on the shores of Lake Tenochtitlan in Mexico, they invented their method of growing vegetables and fruits. The Aztecs built rafts of reeds and lined them with silt from the bottom of the lake, growing fruit trees and vegetables.
Later, in 1860, the Germans Sachs and Knop were the first to grow plants in a nutrient solution, calling the process nutriculture. In 1938 WF Gericke, a professor at the University of California managed to successfully establish commercial soilless cultivation units, baptizing this production system as hydroponics and is considered the father of this modern cultivation technique.
Subsequently, commercial hydroponics spread throughout the world in the 1950s. The NASA space agency carried out the first serious research in modern hydroponics in the late 1960s and early 1970s in the United States.
Man cannot survive in space without the means to produce fresh food. NASA has even done experiments to grow plants in zero gravity. On planet Earth, at remote scientific stations in Antarctica, the Arctic, and other inhospitable places, hydroponics is used to grow food supplements.
Russian station in Antarctica assembled the hydroponic system. The greenhouse room, shaped like an igloo, was also equipped with hammocks for the expedition members, who could rest and warm up there. However, the main achievement was the supply of basic foodstuffs, which were priceless during a long expedition.
Hydroponics has a place in the tourist islands of the Caribbean. The land there is scarce, saline, and unable to provide large numbers of tourists with fresh vegetables, mostly imported but grown on the islands with hydroponic technology at a lower cost.
Some experiments are being carried out on equipping shelters with hydroponic installations in case of an earthquake or typhoon. Within a little over a month, the population can restore a small part of the family garden by applying the principles of hydroponics. Such an experiment was held several times in South America.
A particular group from the Institute of Simplified Hydroponics – is developing “low-tech hydroponics” for third-world countries. They carry out projects on different continents.
Myths and Truth about Hydroponics
Hydroponics is still a relatively “modern” technique; some people are afraid and do not understand what it really is, which creates myths around the technique, contributing to the rejection by consumers. Therefore, there is an increasing need to clarify some myths and truths related to the technique to extinguish this taboo.
1. Hydroponics produces more than conventional cultivation
Compared to conventional cultivation, its productivity can increase from 30% to 50%. The cycle of hydroponic plants is carried out in less time; they grow much faster than those produced in the soil.
They are super healthy because they get everything they need through much greater nutrient solution control and are free from many vectors and diseases caused by contact with the soil.
2. The technique makes excessive use of water
Hydroponic cultivation is highly efficient in using water. It uses, on average, 70% to 90% less water when compared to conventional cultivation, as the loss of water occurs only through evaporation.
3. Hydroponics is harmful to the environment
Hydroponics is more environmentally friendly than any other type of agriculture. In addition to water retention, the nourishing substances are contained in a closed circuit, preventing soil and water contamination with fertilizer leaching.
4. The hydroponic product has superior quality and appreciation
By growing in a controlled environment, where plants are fed with all the nutrients they need and in the right amount, hydroponic products have better size, appearance, and quality.
In addition, the shelf life is longer, as they are usually sold with the roots still, not soiled with soil, which does not allow an outlet for the internal fluids of the plant. Hydroponic lettuce, for example, achieves sales prices 35 to 50% higher than conventional lettuce.
5. The cost of labor is higher compared to conventional cultivation
The workforce is reduced since many automated production processes are developed, such as fertilization and irrigation.
In addition, handling can be done standing at a comfortable height for work, as benches are used in the laminar flow technique.
6. Less risk of pests and diseases on the plantation
The risk of contamination and disease is much lower by staying away from the soil, where the pathogens are. Pest detection and control are also more efficient than any other agricultural technique.
7. It is possible to obtain year-round planting
Unlike conventional agriculture, which depends on climatic conditions, hydroponics allows planting during all months of the year, as the environment is protected and controlled.
8. Maintaining a hydroponic grow is expensive
Because it is easy to grow, maintenance time and costs are significantly reduced. There are initial investment costs, such as materials, but this type of cultivation allows for greater production in less time, obtaining a relatively quick return.
9. Hydroponics is only viable for leafy crops
Although leafy vegetables are predominant, especially lettuce, practically everything can be grown using the technique: watercress, melon, cucumber, string bean, cabbage, strawberries, tomato, pepper, eggplant, rice, ornamental plants, tree seedlings, among others.
10. Light is not essential in hydroponic growing
Light is the main factor that triggers photosynthesis, which allows the fixation of carbon in plants, so it is essential to observe the location and positioning of the hydroponic structure, to make the most of solar radiation.
However, excess light and solar radiation can harm plants through excessive water loss in the tissues, heating the nutrient solution, or several other factors. Therefore, it is vital to place suitable greenhouses, screens, and films to ensure adequate lighting for the growth and production of plants.
Functioning of Hydroponics
The hydroponic method is characterized by growing plants through water. Germinations typically occurs in a separate location with minimal space in phenolic foam boards.
After germinating, the seedling is transplanted to the environment where it is likely to develop. The implantation of the nutrient solution begins, which is composed of pure water and fertilizers.
Each vegetable variety has its own growing time and nutritional needs. It is possible to control the amount of minerals and soluble solutions so that the plant develops acceptably. The light requirement is part of most plants, and when natural sunlight is not possible, artificial light is implemented within the plant’s need parameters.
Difference Between Traditional and Hydroponic Agriculture
The main difference between conventional and hydroponic gardens is that water is used differently, not to mention the absence of land in the hydroponic system. The hydroponic system delivers the water more efficiently, with a higher percentage of water going to plant evapotranspiration.
Hydroponic plants grow faster than soil-grown crops, allowing for more crops per year and faster profit. Conventional farming is limited to growing seasons, while hydroponic growing can be done indoors all year round, regardless of outside temperatures.
Cost to set up Hydroponic
One of the main things you must consider is the cost required to deploy a hydroponic system. You’ll need pumps, tanks, and controls for the system, which can easily cost several hundred dollars for every square foot of growing space. Therefore, the initial investment is high.
Low-tech hydroponic systems are budget options purchased as a unit or hand-built. You can buy a low-tech hydroponic system for around $50 to $200. We must also consider the cost of running the system, and they are usually higher than in traditional agriculture.
Benefits of Hydroponics
Traditional plant growing is an exciting and educational option, but the truth is that by comparing it with hydroponics, we can immediately see that it has many advantages:
1. Improved absorption of nutrition
The plant no longer expends vital energy on developing the root system; the hydroponic mixture provides all that is needed. The energy consumption required for the development of the root system is minimal.
The energy is entirely focused on developing its above-ground part, due to which the growth rate increases and the yield increases.
Also, these indicators are positively affected by the absence of soil, which acts as a buffer that slows down the process of absorption of the necessary chemical elements.
Representatives of the flora directly receive all the necessary substances from the nutrient solution.
2. Same species can be grown over and over again
The nutrients available in the ground are depleted as they are taken up by the roots, forcing every gardener, farmer, or hobbyist to fertilize the soil repeatedly. This problem with hydroponics has been eliminated, and the ability to grow the same species as many times as we want.
3. Culture media control
Thanks to the hydroponic method of growing, the grower gets the opportunity to strictly control the types and dosage of nutrients, giving each specific plant only the necessary chemical elements for its comfortable development.
In case of an overabundance or lack of nutrients, it is only necessary to replace the solution promptly.
4. Cleaner and more practical
As for the positive aspects for the gardener himself, he does not need to work with the soil. The growing area becomes cleaner.
Hydroponics also allows a more rational use of free space. The roots of the plant require much less space.
5. Water saving
A plant must transpire a certain amount of water to maintain healthy growth. The rapid, lush growth in hydroponics requires the consumption of large amounts of water.
However, the plant transpires all the water used up. Nothing disappears in the soil or by evaporation. Compared to plants growing in the soil, the water savings are quite impressive.
Recent improvements in irrigation – moving from irrigating the entire field to delivering water to the base of the plants – have significantly increased water use efficiency in horticulture. However, hydroponics is still much more effective in this regard.
6. Improved health and faster growth mean less need for pesticides
Many people imagine that pesticides only kill pests. However, their action is not selective, and they also kill beneficial organisms. We should limit their use to exceptional cases.
The fact that a hydroponic plant, when properly cared for, proliferates and does not get sick allows it to outgrow pests or at least resist them.
It doesn’t mean that you won’t need to deal with pests again, but there will be less need for this, and you will be able to solve problems with more gentle solutions without destroying all life in the plant’s environment.
Of course, this applies mainly to fast-growing annuals. It is debatable in the case of perennials, although the vitality of a hydroponic plant also helps here.
7. Bigger size, better quality
One thing is clear: if you strengthen the plant’s health, then productivity and yield will increase. Hydroponic crops are noticeably larger than their counterparts grown in the ground.
And in the field of nutrition, there have been many analyzes that consistently show large, often double, increases in vitamins and mineral salts. It also applies to active substances in medicinal plants.
8. Production of large amounts of biomass
Hydroponics can do it. The high nitrate content in the nutrient solution promotes explosive vegetative plant growth. If you require a lot of green mass, then this is beneficial.
Hydroponic pools are possible to be used to treat heavily polluted wastewater. The by-product will be a lot of green mass, which can be used as fuel when processed.
Many successful experiments have been carried out, for example, in Portugal, where a research institute managed to clean the effluents of a pig farm. They have been transformed into a profitable crop.
Despite the numerous advantages, the hydroponic system presents some of the main problems, including the high initial cost, the need for specialized labor, and much more.
1. Requires a constant supply of water
No plant can grow without water. Remember that hydroponics means growing without soil, but you won’t get anything if you don’t have this precious liquid.
2. Initial investment can be high
A complete professional hydroponic kit costs at least 1000 dollars, which is high for an initial investment. But it’s money that you will eventually recoup as you won’t need to spend it on phytosanitary products if you take care of the details and make sure the water, substrate, and system are clean.
3. Doesn’t forgive mistakes
Plants are not immune to your mistakes; the soil has buffer properties. It means that it can maintain a certain amount of stability around the roots. In healthy soil, all physical and biological parameters are in balance.
If you give your plants too many nutrients, the wrong mixture, or an extreme pH level, then the microorganisms in the topsoil and the soil chemistry will eventually rebalance. The same thing happens in hydroponics systems, but to a limited extent.
The nutrient solution has a specific buffering capacity, especially concerning pH. But on the other hand, an over-scaled pH level can lead to the destruction of the entire crop in one day. In hydroponics, everything happens quickly.
4. Specialized labor
Hydroponics requires skilled farmers to know precisely how to use the equipment correctly, care for each species, and what each needs to ensure maximum yield.
Therefore, this system requires that qualified farmers know what nutrients each species needs to ensure maximum efficiency, which can be more expensive in terms of the total expenses of those seeking to adopt this system.
5. Risk of loss due to lack of electricity
Another risk to hydroponics and greenhouse growth is that all your plants depend on the electrical grid.
Unlike outdoor growing, where sunlight and air movement are natural, in the hydroponic system, if there is a short-term power outage, your plants will lose light, airflow, humidity controls, temperature, and nutrient controls during this time. It can be devastating for cultivation.
Varieties of Hydroponic System
There are mainly six varieties of the hydroponic system:
1. Periodic flooding
This method is very simple and consists of liquid flow from one pot to another. Like everything in our world, this method has its pros and cons, the most important: the availability of the system and low costs.
However, constant monitoring of the quality of solutions is necessary since the risk of water contamination with pathogenic microflora is very high.
2. Deepwater culture
It belongs to active systems; in terms of its structure, it has not far departed from the periodic flow.
The main set includes a compressor that supplies oxygen to the solution, thereby feeding the root system of plants, which are located in special pots and fixed in the tank lid.
The advantages include the simplicity and cost-effectiveness of this method, which is excellent for beginners who are just discovering the mysterious world of hydroponics.
But let’s not forget about the “dark side” – a large amount of moisture and the lack of regular cleaning can lead to root rot and the loss of the entire crop.
3. Drip irrigation
Each grower has its own “tricks” in organizing this system. However, a properly organized system practically does not require human intervention in the irrigation process. However, this is also the “Achilles’ heel” of the system – it needs regular cleaning from blockages.
4. Nutrient layer technique
Plant roots are placed in an irrigation canal, and a nutrient solution is supplied by a pump on a continuous or intermittent basis. The rest of the nutrient solution flows back into the tank, and then the cycle repeats.
The advantages include active oxygenation and rational use of the nutrient solution. The disadvantage includes blockages. And also, any technical malfunctions associated with the operation of the pump can lead to crop loss.
5. Wick system
Cheap and cheerful, and most importantly, simple, and it works. All that is needed is a pot of substrate and a wick dipped into the nutrient solution.
Under the influence of the laws of physics, the liquid rises the wick. Obvious advantages – there is no need to use technologies (pump, sensors), which allows you to save a lot.
The downside is the lack of nutrient recirculation due to the lack of a pump—a slow growth rate, which may discourage beginners from associating their hobby with hydroponics.
It is a relatively young method of growing plants without using a substrate. The roots are in the air space and are regularly irrigated with a nutrient solution in the form of an aerosol.
The bowl is used on an industrial scale and allows you to achieve excellent results in growing, but no one will forbid you to grow in this way at home.
The obvious advantages are unlimited access to oxygen in plants’ roots, maximum absorption of nutrients, and rational use of space. The disadvantages are the lack of the possibility of using thick nutrient mixtures and system blockages.
Hydroponic System at Home
If you are determined to grow your food and hydroponics seems the best option, you will need several elements to make the assembly. In general, they are easy to get.
However, there are various structures to have a hydroponic crop at home with difficulty levels that range from simple to complex. It is even possible to purchase systems for hydroponic cultivation in home stores.
Regardless of the system used, it must be located where it can receive sunlight for at least 6 hours a day. Likewise, we must protect it from possible damage caused by winds, heavy rains, or domestic animals.
Materials You Need
- Large opaque container. It must be dark for the roots to develop properly.
- Top or wooden board. The exact size of the container.
- Oxygenation pump, like the ones used for aquariums.
- Vegetable sprouts.
- Nutrient solution. You can get it at agronomy and cultivation stores or online.
- Plastic lid.
- Substrate for hydroponics. There are different types: coconut fiber, clay, rock wool, or perlite stones.
Steps to follow
- You must make a hole in the container suitable for the size of the stopper you have selected. This hole will serve to drain the water and change it.
- Take the wooden board or the container’s lid and make holes with a distance of approximately 10 to 20 centimeters between them, depending on the expected growth of the vegetable you want to plant.
- Secure the plants with the substrate by the stem to give them stability and allow them to absorb nutrients well. Allow the roots to grow long.
- Insert the roots being careful not to damage them between the holes in the board or lid of the container.
- Oxygenate the water 2 times a day with the aquarium pump.
Frequently Asked Questions (FAQs)
1. How nutritious are vegetables and fruits are grown hydroponically?
Such vegetables and fruits are no different or even superior in nutrition to ordinary vegetables and fruits, provided that they are grown according to the correct technology and eaten fresh.
Any vegetable or fruit loses its nutritional value the longer it is stored before being eaten. When the fruits and vegetables get on the shelf in the supermarket, vegetable fruits “travel” for a long time.
During their journey to the consumer, they may lose some of their nutritional value, and their palatability may suffer.
2. How does the taste of hydroponic grown vegetables and fruits differ from those grown in normal soil?
There is an opinion that hydroponic products are tasteless. But that is not the case at all.
Hydroponic grown vegetables and fruits are not inferior to the usual taste, provided that the cultivation technology is strictly observed.
If a vegetable or fruit is grown in hydroponics, but all the conditions for the optimal development of this plant are not met, then the vegetable or fruit from such a plant will be tasteless.
3. Is it true that plants grow faster in hydroponics?
No, not all hydroponic plants grow faster. Several plants (such as ferns) grow in the same way in soil and hydroponic, growing under the same conditions.
Ornamental plants and vegetables typically grow faster than their “soil” counterparts.
In hydroponics, plants do not have to compete for nutrients as they do in soil; they get everything they need from the nutrient solution.
4. Hydroponic fruits and vegetables are said to be much larger than regular ones. Is it really true?
Growers who do hydroponics as a hobby get larger fruits than usual. Large greenhouse farms regulate fruit sizes according to market demands.
In the arsenal of specialists, there are many tools for controlling fruits’ size, shape, color, and consistency.
5. Is hydroponics suitable for any plant?
Most plants do not resist growing hydroponically. But not all hydroponic systems are suitable for every one of them. For example, lettuce grows faster in a water system, while grapes prefer the substrate.
The only exception is mushrooms, whose nutrient requirements are very different from plants. Therefore, they cannot be grown hydroponically.
6. Can inorganic substances used in hydroponics be harmful to health?
Definitely not. Hydroponics uses the same inorganic substances that plants get from the soil.
When fertilizers or manure are added to the soil, it takes a long time for the appearance of inorganic substances that plants need. In hydroponics, plants get these substances directly from the solution.
7. How much nutrient solution does the plant need per day?
The absorption of water macro-and microelements from a solution by a plant depends on the processes of photosynthesis and respiration, which, in turn, are determined by several factors:
- the size and volume of the plant’s leaf crown,
- the intensity and duration of illumination,
- air temperature,
- relative humidity and
- air movement.
For example, the same plant will need different amounts of water and nutrients in dry and wet environments. In the first case, the amount of absorbed water and substances will be higher.
Compared to growing a plant in the shade, the plant’s absorption of water and substances will also be higher if the light intensity is high.
8. Is it possible to reuse the plants’ substrate?
It is possible if the previous plant did not have diseases, especially in the root system. Usually, the substrate is sterilized before reuse.
9. How expensive is hydroponics?
It all depends on the size and level of automation of your system. For professional growers with hydroponics as their main line of business, the cost of a hydroponic system is an investment in the quality of the resulting product.
In addition to the cost of the system, we must also take into account the cost of “consumable” materials (water, electricity, fertilizers). The key to the success of hydroponic farms is the knowledge of plant growing technology and constant quality service.
10. Does hydroponics have a future? Maybe it’s a new fashionable thing that will lose interest in a few years?
Hydroponics has long been recognized as a practical and affordable method for commercial and home-growing plant foods.
Currently, more than 70% of all greenery and ornamental flowers sold worldwide are grown hydroponically.
In addition, hydroponics is actively used in regions where traditional farming is impossible (arctic or arid regions of the planet). From an ecological point of view, hydroponics contributes to the conservation of water resources.
Hydroponics is an excellent option for all types of producers. It has several advantages and can meticulously control the variables that affect plant growth.
A well-maintained hydroponic system can easily outperform a conventional system in both product quality and quantity. It may seem intimidating at first with all the equipment, planning, and investment involved, but once installed, you can see the quality of the technique.
(Last Updated on June 14, 2022 by Sadrish Dabadi)