What Are The Most Common Forms of Hydroponics

Jul 08, 2022

Discover the multiple types of hydroponic methods that are used to grow plants in both private residences as well as large commercial growing operations.

There are many forms of hydroponics that can be applied in numerous applications both privately and commercially.

Aeroponics – roots are sprayed with a mist

The aeroponic method of cultivating plants utilizes a form of a frame or enclosure to secure the plant, allowing the roots to be suspended in the air and sprayed with a mist of nutrient-rich water. 

Aeroponic hydroponics allows the roots to grow down and absorb the nutrients in the misting water and the plant to grow upward, producing fruit. Exposing the roots of the plants allows them to absorb maximum amounts of oxygen which aids the root system in consuming the nutrients in the water, stimulating growth. The frames that hold the roots are a container to keep out light. Light is essential for growing plants, but it isn't good for the roots to be exposed to it. These containers block the light to the roots but mist the nutrient-rich water hundreds of times daily, allowing oxygen to flow through them.

The size of the water droplets (too tiny the plant is stunted and too large the plant can get mold/mildew/over watering) and how often the roots are misted is very delicate. In advanced systems that are computer/timer controlled, the misting turns on for a few seconds and then off for several minutes. This misting on and off-cycle occurs hundreds of times during the day.
The advantage of aeroponics is the ability to grow plants quickly with air as the medium. When growing plants in the air, there is nothing to inhibit the plant's growth, so all the plant's energy goes to growing which usually results in high yields.

Deep Water Culture Hydroponics – roots submerged in nutrient rich water


Deep water culture hydroponics is soilless in which the plants are placed in a medium or root nets to secure them. The plant roots are submerged in nutrient-rich water with an air stone in it with a tube attached to a pump that sends oxygen into the tank, aerating the tank with oxygen. The roots use oxygen to absorb and convert the nutrients into food to grow faster and more significantly than plants grown in soil. Deep water culture hydroponics is used in homes and commercially. The best plants for deep water culture hydroponics are lettuce, spinach, herbs, strawberries, and bell peppers.

Deep water culture hydroponics is easy to set up, and the only electric part is the air pump which must run constantly. Because the same water is reused, the pH and nutrient content must be monitored regularly. Plants use more of some nutrients than other nutrients depending on what growth cycle they are in; that is why it needs to be monitored closely. If the pump should fail or the electricity goes off, the root system will not survive sitting in stagnant water. Stagnant water will rot the roots as it becomes a prime breeding ground for bacteria and fungi.


Drip Hydroponics – most water efficient


Drip hydroponics is the most popular system because it is the easiest and most water-efficient irrigation system. This form of hydroponics is used in city apartments to the largest commercial hydroponic farms in the world.

There are vertical and horizontal drip hydroponic growing systems that allow the nutrient water to seep through the growing medium to the base, and the excess water can be reused or discarded. There are two types of drip hydroponic systems: recovery and non-recovery.


Drip Recovery Hydroponic Systems

The recovery drip hydroponic system is when the nutrient-rich water is recovered and recycled back through the drip system and used over again.

This irrigating recovery system makes it the most water-efficient, and it puts back into the system any unused nutrients, thus saving money. The recovery system is the least dependent on technology between recovery and non-recovery drip systems. The recovery system is dependent on gravity. The nutrient solution is dripped into the top of the single pots or vertical towers, and it seeps through to the bottom, watering all of the plants as it descends downward. It then empties into holding containers to be pumped back to the drip emitters at the top. This method eliminates a lot of nutrient waste but requires careful monitoring of the pH levels and nutrients in the water.


Non-Recovery Hydroponic Systems

The non-recovery hydroponic system works the same way as the recovery, except that a grower needs to be more precise on how much nutrient water is dripped and how often.

The non-recovery drip system is technology dependent with cycle timers and irrigation amounts so that it is regulated down to the second. There is hardly any excess water left over, making it more resourceful than other hydroponic systems. The excess nutrient water is disposed of when it reaches the bottom of the pots or vertical towers. By not recovering any excess nutrient water, there is no need to monitor the reservoir's pH levels and nutrient levels. The automated reservoir always has a precise combination of water and nutrients.

Whether you use the recovery or non-recovery drip hydroponic system, it is easy to use, and you can grow plants all year round. In this system, you do not have to worry about the roots drying out should there be a power outage for a short time as the growing medium will keep the roots moist (unlike using aeroponics which has to worry all the time about the roots drying out).


Ebb And Flow Hydroponics – repeatedly flooding the roots


Ebb and Flow or Flood and Drain Hydroponics are often associated with aquaponics (the use of fish waste nitrates flushed through the hydroponic system watering the plants).

Ebb and flow hydroponics are soilless. The plants are grown in some medium (some mediums are: clay grow stones, sand, rock wool, and rinsed gravel) in individual containers or frames that sit on tables (these are just two examples) so that the root systems can be flooded with nutrient-rich water and then the water drains out (this is the ebb and flow or flood and drain effect). The roots get flooded, and then the water is drained off to allow the medium to dry out and the roots to grow and search for water, and then they are flooded again. The more the plant's root system increases, the bigger and healthier the plant is. The more extensive the root system, the more nutrients it absorbs.

The ebb and flow system works when the timer turns the pump on, the water is pumped through the tubes to fill the plants' containers until it reaches an overflow tube at the top of the containers. When the water reaches the overflow tube, it will drain back to the reservoir, thus keeping the water level at the same height so flooding doesn't occur. The timer will continue to enable the pump to be on and pumping until a specified time; then, it will turn off. When the timer shuts the pump off, the water in the growing containers will drain back to the reservoir through the tube that brought it in because there is no pressure to "push" it into the container; therefore, it ebbs back to the reservoir. This form of hydroponics needs its pH frequently checked since it recycles the water and is prone to algae in the reservoir tank.

Ebb and Flow hydroponics are popular because you can use basic materials easily purchased from local stores. Ebb and flow hydroponics are very versatile in size, so this form of hydroponics is used in apartments and commercially. Ebb and flow hydroponics have excellent success with larger plants such as tomatoes and cucumbers.


Fogponics – using fog instead of mist


Fogponics is a sub-family of aeroponics.

Fogponics, as with aeroponics, is plants growing in the air. The plants are suspended in containers, and a fogger is used to transform nutrient-rich water into a nutrient-rich fog released into the air. This nutrient-rich fog creates humidity, and the growing area resembles a rainforest.

Fogponics is new, and probably the least used at this time. However, experiments are being conducted daily with improvements, which could be the future of hydroponics.

Nutrient Film Technique – a flowing river in chambers


Nutrient film technique hydroponics is soilless hydroponics. The technique utilizes tube-like chambers set at a slight slant so that the nutrient-rich water can flow continuously through them. The plants can be in a medium or the roots hanging freely with the plant held in a net pot. Using net pots is the most common way. The "tube chambers" can be only so long to ensure that all the plants receive ample nutrients as the water flows through the chambers like a stream. This "flowing river concept" captures oxygen which the roots use to absorb more nutrients from the water, causing them to grow faster.

NFT hydroponics is simple to use and recycles everything that is left over. Because the nutrient-rich water flows from the reservoir up to the high end of the tube chamber and runs down to the low end, emptying into the reservoir requires no timers or watering cycles. NFT uses less water and nutrients since it is a constant recycling system, and algae don't grow in the reservoir because it is continuously being pumped out and flowing in.

This system is best used for smaller plants such as lettuce and herbs as they will be harvested before the root systems get too big for the tubes. Growing tomatoes and other fruiting plants in this system require frequently checking the pH levels because they are heavy feeders. Tomatoes and other fruit-bearing plants' root systems tend to get too big for this system. Experiments have proven that fruiting plants must have the root systems dry out between watering cycles to provide the best growing environment.

In NFT hydroponics, the pump does run all the time, and if there is a power outage or the pump fails, this could cause the roots to dry out and the plants to die.


Wick Hydroponics – no moving parts


Wick hydroponics is the simplest and easiest hydroponics.

Wick hydroponics consists of four basic components: a growing container, a growing medium, a reservoir for the nutrient water, and wicks. Wick hydroponics is a passive form of hydroponics, meaning there are no moving parts, no motors, and no pumps. This doesn't mean that you can't use an air pump to add oxygen to the water, but in the simplest form, you don't have to.

In wick hydroponics, the plants are placed in a container with a growing medium with a wick (any material that will absorb water) running out of the growing medium into the reservoir of nutrient water. The wick will absorb the water into the medium, thus watering the roots. This "wicking" or "capillary action" delivers the liquid to the roots without the help of any other component, including electricity. The primary upkeep for this system is to refill the reservoir and clean the reservoir regularly.

Wick hydroponics is probably the most environmentally friendly hydroponic system because it doesn't use electricity, the components can be from recycled items, and it uses less water and nutrients than all the other hydroponic systems. Smaller plants such as lettuce and herbs are the best plants to grow in this system.


Indoor growing with hydroponics and led grow lights.


Whether growing in your house or commercially, there is a hydroponic system that will fit your needs. Hydroponics offers an ideal system for growing indoors all year round with full-spectrum LED grow lights. This lighting provides the ability to succeed no matter what season it is.

Hydroponic growing delivers to the root system everything the plant needs to grow faster and more superior than soil-based plants. Soil-based plants have to work to find nutrients in the soil instead of having the nutrients applied to the roots, thus allowing the plants to expend their energy on growing and producing instead of searching for nutrients.

Hydroponically grown plants grow 30 to 50% faster than soil-based plants. Growing plants hydroponically allows for more crops to be grown one after another.