A hydroponics system is a closed-loop system that provides plants with water and nutrients without the need for soil. Hydroponics can be considered an agricultural technique, as well as a branch of hydroculture, the cultivation of living organisms in water.
The first known published work on growing terrestrial plants without soil was “French Dirt” (1951) by George de Mestral. The growing plants are usually supported by some sort of rigid porous material to hold up the plant and to keep it away from contact with the nutrient solution, although larger plants can be contained within a cloth container or basket and then immersed in solutions that contain minerals and nutrients; these systems are sometimes called “submerged systems”.
Hydroponics was used extensively in the early days of space exploration. Plants were grown for food and oxygen production, but also to supply oxygen to astronauts and provide a source of fresh water on Mars.
In hydroponics, there are several methods including:
NFT = Nutrient Film technique
In the soil-less method, the roots are suspended in water without compacted soil. Soil-less growing may be done with plastic or glass containers or on mats energized with light or electricity, with no material needed for support such as stakes. This allows the roots to be below the water line, and makes it possible for a great number of plants to be grown in a very small space.
A sub category of soil less, is the Nutrient Film Technique (NFT) in which the plant’s roots dangle into an aerated trough where they are sprayed with nutrient solution.
This technique is used for the production of high-value crops such as vegetables in greenhouses. The term “vertical farming” accurately describes this method. A soilless medium is any growing medium that does not support soil life, and therefore lacks structural integrity when used on its own. The soilless mediums that are used are usually composed of a mixture of sand and vermiculite, perlite, rockwool, coco fiber, wood fiber or plastic foam.
BCP = Bubbling compost tea system
A bubbling compost tea (BCT) system supplies nutrients to plant roots in liquid form as water is pumped through an aerated tank containing composting materials. The nutrient-rich water goes through carbon filters into a pump that pushes it to the plants.
The pump also recirculates water within the tank, keeping solids suspended in the water and providing oxygen to the microbes in the compost as they break down organic material. The composting process also absorbs nitrogen from the air and adds it to the mix, while also providing other nutrients such as phosphorus and potassium.
This method is used for indoor gardening. Water is pumped by a pump through a bubbling system where it passes through compost and bacteria, removing impurities from the water. The high oxygen level keeps worms alive in the compost, while oxygenating the water. The bacteria produce chemical substances that break down organic matter, producing rich liquid fertilizer for plants such as tomatoes and peppers; these liquid replicas of soil are called B-Cups (short for bio-compost cups).
The BCP is an alternative to using ponding systems because there are no nets or leaves to obstruct nutrient flow. The BCP is also easier to create and maintain. It is generally used indoors, with multiple plant varieties being grown in a single system. It can be waterless because of its aeration system, or it can be water included as long as the aeration is strong enough to provide extra oxygen.
The active hydroponic method uses a grow medium that provides the necessary nutrients to the roots by means of biological synthesis. The roots do not have to be immersed in nutrient solutions and they are able to obtain free-flowing oxygen via gaseous exchange, similar to the methods employed in soil-based aquaponics systems. This is a low-cost method, with the plants not needing to be grown in pots filled with a growing medium.
The method has been used successfully for growing indoors, but is not suited to farming outdoors. This method works best in warm temperature environments where there are few pests and diseases.
Aeroponics is a technique of growing plants in anaerobic environments where there is no root-zone soil. Aeroponic systems are usually fed by liquid nutrient solutions or inert gas mixtures, instead of relying on rainfall as does soil-based agriculture. The most common application of aeroponics is for indoor gardening, but it can also be used for outdoor agriculture. The two main methods of aeroponics are “pot farming” and “tray farming”.
Aeroponics is also one of the 2 leading systems used in space exploration: The other is hydroponics, which is used for growing soybeans and cotton.
Micro-hydroponic systems are designed to be small enough to be produced and run by individuals or small groups of manufacturers. These systems use a self-contained nutrient solution directly delivered to the roots without the need for soil or dirt media. In this method, plants are grown in a plastic bag or fabric-like container with holes poked in the top.
The systems use the available nutrients in the micro-water and live root supplies to grow plants through a process known as photosynthesis. The roots of the plants penetrate into this media and begin the absorption of water and nutrients from the medium. The system provides a steady source of nutrient solution for each individual plant without the need to replenish manually.
Another variation is Aeroponics, where a “culture” (plant) is grown in an aeroponics chamber with no soil, instead of growing in a tray or pot. This is often used for indoor gardening but can also be used for outdoor agriculture as it is lightweight and can be set up almost anywhere.
One of the advantages of micro hydroponics compared to photoperiodic methods, such as the mainstay of indoor gardening is impressive color production. Indoor growers can achieve full spectrum colour from reds to pinks through a range of plants and techniques.
The richer hues can be achieved by using high quality LED lights, further assisted by modern ballasts which save energy by allowing micro-lights to be dimmed. The technique is getting more and more popular but will still not give the end user near the same light spectrum as indoors growing with natural sunlight.
Aeroponics is a closed systems where water and nutrients are delivered directly to the roots for plant growth through an inert gas (usually nitrogen) mixture. This differs from traditional hydroponics, in which water goes to the roots and nutrient solution goes up to the leaves.
However, it is not an entirely closed system, as carbon dioxide is used in the growing media. The main reason for using gas instead of water is that there are no problems with respiratory pathogens or bacteria getting into the air supply. This method produces a very high quality yield at a low cost per plant.
Aeroponics has low light intensity compared to other techniques and therefore requires high quality lighting to provide sufficient light during production. The power needed can be reduced by installing bespoke reflectors inside your container.
Aeroponically grown plants are generally smaller than those grown in other methods. This is due to lower oxygen concentrations making it harder for the plant to grow roots which are responsible for absorbing water and nutrients. Feeding roots with a solution of oxygenated nutrient provides support for root growth and therefore size.
Aeroplant is one of the few companies in Europe that designs, develops and manufactures aeroponic systems for both indoor (IAC) and outdoor (OAC) use, i.e. Aeroplant OAC-1 (Outdoor Aeroponic Cultivation System – 1 plant) up to large scale aeroponic farms with a capacity of over 50,000 plants per year (e.g. Aeroplant OAC-50 (Outdoor Aeroponic Cultivation System – 50 plants) and Aeroplant OA-100 (Outdoor Aeroponic Cultivation System – 100 plants)).
What are the benefits of growing in aeroponics?
Aeroponics allows the production of plants in a controlled environment at an optimal temperature and humidity. This is ideal for the production of seedlings and cuttings, as well as for obtaining large plants at a very low cost per plant (i.e. less than $0.2 per unit).
The plant is grown in a net pot that is hung inside a growing chamber. The roots are sprayed with nutrient solution at regular intervals by jets positioned above the roots. Best of all, aeroponics allows for the production of plants year-around regardless of weather conditions.
The Grow Room hydroponics system uses this technology to produce the highest quality produce and flowers, without the use of pesticides, and with minimal water usage. The Grow Room is specifically designed for medium- to large-scale operations. It can be scaled with multiples of units used together in a series, increasing your production capacity along the way, or as you grow.