Can you imagine growing crops without soil? Well, that’s what hydroponics agriculture is all about.

The Portuguese proverb that the chicken that stays in the farmyard will peck the crumbs, emphasizes on the importance of farming for our survival as humans. Although most people tend to find farming tiresome and sometimes a boring task to do, we ought to embrace it as it is critically important.

 

This article tends to inspire those people who view farming in a negative way probably because they are allergic to soil, grass, the sun,  are afraid of earthworms or ploughing and many other reasons. It presents hydroponics as an interesting method of farming, which shifts from the common way of farming (soil farming).

 

Before diving into educating you on hydroponics (what it is, how it works, its types, benefits), we thought it best to take you through the journey of hydroponics (its origins, development and how it became popular).

 

Hydroponics means working with water (Hydro means water and ponos is labour).

 

Many civilisations have utilised hydroponic growing techniques. Hydroponics is an ancient method of growing plants dating back from the gardens of Babylon. The floating gardens of the Aztecs of Mexico are also examples of hydroponics culture.

 

Hydroponics was used during World War  II to supply troops stationed on non-arable Islands in the pacific with fresh produce grown in locally established hydroponic systems. Throughout the last century, scientists and horticulturists experimented with different methods of hydroponics.

 

Traditional  farmers and eager hobbyists began to be attracted to the virtues of hydroponics which this is now being used even today, with commercial growers flocking to hydroponics like never before.

Hydroponics is a subset of hydroculture  (the growing of plants in a soilless medium, or an aquatic-based environment)  is a method of growing plants using mineral nutrient solutions, in water, without soil.

Not all plants grow fast and healthy when hydroponically grown, although most of them do like herbs and greens such as strawberries, tomatoes, mint, basil, lettuce, cabbage, green beans and many others.

 

The bottom line is it depends on the nutrient solution the vegetables are grown in, but hydroponically grown vegetables can be just as nutritious as those grown in soil. Plants make their own vitamins, so vitamin levels tend to be similar whether a vegetable is grown hydroponically or in soil.

 

If you’ve ever placed a plant clipping into a glass of water in the hopes that it will develop roots, you’ve practised a form of hydroponics. The nutrients that the plants normally derive from the soil are simply dissolved into the water instead, and depending on the type of hydroponic system used, the plant’s roots are suspended in, flooded with or misted with the nutrient solution so that the plant can derive the elements it needs for growth.

vegetables grown using Hydroponics In ZImbabwe
vegetables grown using Hydroponics In ZImbabwe

 

As the population of our planet soars and arable land available for crop production declines, hydroponics will offer us a lifeline of sorts and allow us to produce crops in greenhouses or in multilevel buildings dedicated to agriculture.

Already, where the cost of land is at a premium, crops are being produced underground, on rooftops and in greenhouses using hydroponic methods.

 

Benefits Of Growing Plants With Hydroponics

By using hydroponic gardening; you can raise your plants anywhere, as long as their growth requirements are met. Here are some of the benefits specifically for hydroponic gardening.

 

  •  Requires less water and this is critical in these days when climate change is leading to a lot of droughts.
  • Crops grow faster and healthier. Some reports suggest that crops grown using hydroponics grow up to 33% faster. That’s great news for farmers as they can have shorter turn around times.
  • You can use 20% less space compared to soil-based gardens
  • It provides a clean environment for plant production. This means that your hydroponic garden has no need of pesticides, fertilizers or other chemicals because it cannot catch soil-borne diseases or pests.
  • You lose valuable nutrients in soil-based gardens due to run-off. Calcium, phosphorous and potassium content often dissolved in it. However, in hydroponic systems; water may be reused multiple times which conserves water and the expense incurred from it.
  • It is less laborious and harvesting is easier and faster
hydroponics in zimbabwe
A clean hydroponics farm in Zimbabwe

There are 6 basic types of hydroponic systems; Wick, Water Culture, Ebb and Flow (Flood & Drain), Drip (recovery or non-recovery), N.F.T. (Nutrient Film Technique) and Aeroponic. There are hundreds of variations on these basic types of systems, but all hydroponic methods are a variation (or combination) and they are explained below:

 

Wick System

The Wick system is a simple and passive type of hydroponic system. The mechanism of delivering the nutrients and water when using a wick system is that they are drawn in via the growing medium. This system avoids the need to have any pumps to circulate the water and nutrients to your plants.

 

The Wick System in Hydroponics
The Wick System in Hydroponics

What kind of medium can you keep your plants within this system? There are quite a number of potential materials which can be used as a growing medium for wick system hydroponics. Vermiculite, Perlite, Pro-Mix, and Coconut Fiber are some of the most popular. One potential drawback of wick systems is that large plants or plants that use a lot of water may use up all the nutrient solution quicker than the wick(s) can resupply it.

 

Deep Water Culture

Deepwater culture systems are another very simple way of growing plants with hydroponics. The plants are grown in a tank of water and nutrients. The growing medium is often made from a buoyant material so that it is able to float and hold the plants in place, with the leaves above the water and the roots directly in the water and nutrient solution.

 

Deepwater culture systems require an air pump to constantly oxygenate the water via an air stone, to provide enough oxygen to the growing roots. Without this, the plants would be unable to survive.

Deepwater culture systems are some of the easiest to build and can be put together very inexpensively, making them a good starting point if you are looking to have a go at growing plants with hydroponics. If you prefer, however, there are numerous pre-built deep water culture systems available to buy.

Deep water culture hydroponics
Deepwater culture hydroponics system

Deep water culture systems are a great choice for growing leafy greens, and in addition to being a good domestic hydroponic technique, they are in use for commercial growing in many countries around the world. Deep water culture systems are less suited to large plants or plants which are not harvested after a short period of time.

 

Ebb And Flow – (Flood And Drain)

 

The Ebb and Flow system operates by flooding the grow tray with nutrient solution temporarily and then draining it back into the primary reservoir. This is usually done with a submerged pump connected to a timer. The pump is set up so that when the timer turns the pump on, the nutrient solution is pumped out into the grow tray.

 

When the timer runs out, it shuts the pump off, and the nutrient solution flows back into the reservoir. For these systems, the timer is set to turn on and off several times a day. The frequency of these floods depends on the size and type of plants, humidity, temperature, and the kind of growing medium used to hold the plants.

 

The Ebb and Flow system is quite versatile and can be used with many types of growing mediums. The whole grow tray may be filled with grow rocks, gravel or granular Rockwool. Many gardeners use individual pots of growing medium to make it easier to move plants around or even move them in and out of the system entirely.

 

The main disadvantage of Ebb and Flow systems is that they are vulnerable to power outages as well as pump and timer failures. Without regular access to water, the roots dry out quickly. Some kinds of growing media that retain more water, such as Rockwool, Vermiculite, and coconut fiber, but overall, this system requires careful supervision.

 

Drip Systems

 

Drip systems may be the most widely used type of hydroponic system in the world. The concept is similar to growing bean sprouts in cotton in a plastic bag, or even spraying flowers with water to keep them vibrant. Drip systems have a timer that controls a submersed pump. As the timer turns the pump on, the nutrient solution drips onto the bottom of each plant using a small drip line.

 

In a Recovery Drip System, (like the bean sprout in the plastic bag example) the excess nutrient solution that runs off is gathered back to the reservoir for re-use. In Non-Recovery System (like spraying the flowers) the runoff is not collected.

 

The main benefit of a recovery system is that it uses nutrient solution more efficiently. This means you can use a less expensive timer because the system does not require such precise control of the watering cycles. Non-recovery systems need a more precise timer so that watering cycles can be more precisely adjusted to ensure that the plants get sufficient nutrient solution and the runoff is kept down as minimal as possible.

 

The non-recovery system’s main benefit is that it requires less maintenance than recovery systems. Since the excess nutrient solution is not recycled back into the reservoir, the nutrient strength and the pH of the reservoir will not vary. You can fill the reservoir with pH adjusted nutrient solution whenever you want and then forget it until you need to refill it. A recovery system, on the other hand, may have substantial shifts in the nutrient strength and pH levels and requires periodic adjustments.

 

N.F.T. (Nutrient Film Technique)

 

N.F.T. is the kind of growing system most people think of when they picture hydroponics. These systems keep a constant flow of nutrient solution going so there is no timer required for the submersible pump. This nutrient solution is pumped into the growing tray (which is often a tube), and it passes over the roots of the plants, then drains back into the reservoir.

 

It requires no growing medium other than air, which saves the expense of replacing the growing medium after every crop. Often, the plant is supported in something, like a small plastic basket that leaves the roots dangling into the nutrient solution.

 

Even more than the Ebb and Flow systems, N.F.T. systems are very vulnerable to power outages and pump failures. The roots of their plants will dry out very rapidly if the flow of nutrient solution is interrupted.

 

Aeroponics

 

The aeroponic system is probably the most complicated type of hydroponic system. It too, like the N.F.T. system above, uses air as the growing medium. However, instead of having nutrient flowing over the roots in a tube, the roots hang in the air and are gently sprayed with nutrient solution. This usually must be done every few minutes, and, because the roots are exposed to the air, they will dry out rapidly if the spraying cycles are interrupted.

 

This system also requires a timer that controls the nutrient pump much like other types of hydroponic systems. The difference is that the aeroponic system needs a short cycle timer that will run the pump once for just a few seconds every two or three minutes.

 

Are you interested in hydroponics but not quite ready to build your own system? There are plenty of ready-made ones you can purchase. You really don’t have to spend much money to get started with a simple small scale hydroponic system. If you’re looking for something a bit more adventurous, here are some are aquaponic systems, which use fish in the water to help create the nutrients the plants need. If you search online, you will also find countless designs of hydroponic systems that you can build yourself at home.

 

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