Hydroponics is the process of growing plants in water and without soil. While soil is normally used as a medium for transporting water and as a base for anchoring the plants, hydroponics does away with it and instead uses different mediums entirely – even hanging the roots directly into the water in some cases.
This has many advantages as compared with other methods of growing plants and crops. For starters, it means that plants can be grown in areas where it otherwise would be impossible. It’s also particularly useful for growing plants indoors. Hydroponics ironically uses less water than regular agriculture too, which makes it much more eco-friendly and energy efficient.
So how does all this work? And how might you go about starting your own hydroponic farm?
The answer all depends on what type of hydroponics you’re interested in using. There are multiple different types of hydroponics and each works differently in order to keep the plants in place while at the same time providing the oxygen, water, light and nutrients they need.
As long as the plant is growing without soil and is using a nutrient solution, it’s considered hydroponic – the rest is open to interpretation.
Here we will look at some of the most popular types of hydroponics and how they work in a little more detail.
Deep Water Culture
Also called ‘DWC’ or ‘the reservoir method’, deep water culture is perhaps the simplest, easiest and most common method of hydroponic farming. If you have ever seen rows of hydroponic plants stored in (often white) containers, then you have probably seen DWC.
So how does this work? Basically, this system involves the plants being held in containers that allow the roots to remain suspended in the water. This water is of course a nutrient solution that has all the required vitamins and minerals dissolved into it.
To prevent the plants from drowning meanwhile, an aquarium pump is used to keep the solution oxygenated. It’s important to prevent light from penetrating these systems as this can otherwise wreak havoc. The main advantage of this type of system is that there is no drip or spray emitter which can otherwise risk getting clogged. This makes it a good choice for more ‘organic’ nutrients.
This is commonly used due to its simplicity and due to its scalability. However, as with all forms of force multiplier, it also increases the potential damage that can be caused by error. It only takes for your pump to fail and you can use all your plants and crops in as little as half an hour.
This type of hydroponic system is also called NFT and involves a continuous flow of nutrients which runs over the top of exposed plant roots. Here, the roots are kept on a slope which allows the water to keep trickling over due to the force of gravity.
Basically then, the roots are still given a chance to absorb the nutrients but because only the tips are covered in water, they are still able to breathe and there is no danger of drowning. This type of hydroponics encourages a rapid rate of growth.
Aeroponics is different from many other forms of hydroponics in that there is no body of water involved. Instead, this type of hydroponics uses mist. Here, the plants are kept in an airtight container which will need to be glass to allow sunlight through. Then, the mist – which is made of the nutrient dense solution – will be sprayed over the plants and roots allowing them to absorb the goodness.
Interestingly there are actually two different types of aeroponics too. One uses a nozzle which emits the spray and thereby hydrates the roots. The second method uses a ‘pond fogger’. This second type of hydroponics needs a Teflon coated disc to reduce the amount of maintenance required.
There is also a commercialized version of aeroponics which is a great starting point for those looking to get involved for the first time. This is called the ‘AeroGarden’ and requires very little set-up. It comes with lots of support and supplies and is a very good introduction to aeroponics and hydroponics.
Wicking is another good ‘entry level’ form of hydroponics that is great for beginners. Here, a material such as cotton is surrounded by a growing medium. This material is then used as a wick with one end in a nutrient solution and the other end added to the roots of the plant.
You can simplify this system even further too by using a material that works to wick fluids as the medium. This way, you can then use the top portion of that material as the growing medium and the bottom portion to absorb the water and nutrients.
While many different materials will work, materials like perlite or vermiculite. Less useful are even more absorbent materials like Rockwool, coconut coir and peat moss which disk absorbing too much moisture and thus suffocating the plants.
Drip systems work by providing a very slow feed of nutrient solutions a growing medium. Rockwool, coconut coir and peat moss are good choices because they will slowly allow that medium to drain. This system is again simple but as mentioned earlier, there is a distinct risk of clogging which can be devastating.
Ebb and Flow
This system is also referred to as a ‘flood and drain’ system. It works by flooding the growing area with nutrients and water during short intervals and then draining that liquid. This gives the plants an opportunity to absorb the water and nutrients but also provides ample opportunity for them to breathe and recover. The pump here is hooked to a timer which allows precise control in order to provide the plants with just the right amount of nutrients.
This system is best for plants that are used to periods of being dry. In general, some plants are better suited to specific types of system and learning which these are can make life much easier.