Hydroponics is the art and science of growing plants without soil.
Instead of using soil, plants are grown in a nutrient-rich water solution that is delivered directly to the plant roots.
There are six main types of hydroponic systems:
- Wick System
- Nutrient Film Technique (NFT)
- Ebb and Flow
- Drip System
- Deep Water Culture (DWC)
- Aeroponics
Real quick, before I get too far into this article, you may have heard of the Kratky Method, which is an awesome way to grow hydroponically.
But, because it essentially amounts to a plant in water in a container, it isn’t really a “system” per se. This article is about hydroponic systems.
This comprehensive guide will give you an understanding of each type of hydroponic method to help you choose which is best for your situation.
Let’s dive right in!
Hydroponic Method #1: Wick System
As the name implies, this hydroponic method uses a soft fabric string called a “wick”.
One end of the wick stays suspended in the nutrient solution reservoir. The other part of the wick goes into the grow trays where the plants sit in a growing medium.
The growing medium is what the plant sits in as it grows.
The wick is a soft material that is made up of cotton, nylon, or other absorbent material. The wick acts as the means to transport the nutrient solution to the grow trays and plants.
The nutrient-rich water will flow up the wick until the medium on all sides of the roots is soggy. As the medium turns dry, the wick will reactivate and pull the solution to the plants.
The wick system is passive in nature meaning the system works independently of any moving parts.
The passive nature allows the system to be set up very easily. And, because of its simplicity, it is less prone to irregularities, failures, and breakdowns.
Another benefit is the wick system is cost. This method doesn’t cost much to build and is very simple to maintain.
The wick system is arguably the easiest of the six systems, so it is great for beginners.
On the flip side, the wick system does have some considerable downsides. Head on over to this article to understand the challenges of growing with wick systems.
Hydroponic Method #2: Nutrient Film Technique (NFT)
Nutrient Film Technique (NFT) is a simple, effective hydroponic method.
The NFT design is highly prominent among hydroponic growers due to its basic yet highly efficient design.
As you can see in the illustration above, a NFT hydroponic system consists of two separate areas
- A lower area that contains the reservoir
- An upper area where the plants are housed
The lower area is where the reservoir sits. The reservoir will contain your water pump, air stone, and the nutrient solution that will feed the plants.
The upper area will contain a grow tray where your plants will live.
The nutrient solution flows from the reservoir to the grow tray via the water pump and returns to the reservoir through the nutrient return.
Plants with shallow root systems are best to grow in a Nutrient Film Technique system. These include leafy greens like lettuce, spinach, kale, and arugula and herbs, such as basil, cilantro, and parsley.
NFT systems can easily be built vertically unlike heavier systems, such as Ebb and Flow.
Therefore, NFT hydroponics can make use of limited space to produce a lot of plants. This is a great benefit for the urban farmer!
I would suggest NFT as a great option for those people who have some experience with hydroponic gardening and have outgrown some of the easier methods, such as the wick system discussed above.
Although the system is simple to set up, there are some risks and challenges the novice grower may want to avoid. This article explains these challenges in greater detail.
Overall, NFT hydroponics can be a great option for people who want to grow plants in tight spaces in an efficient and environmentally friendly way.
3. Ebb and Flow System
Ebb and flow, also known as the flood and drain system, is an active form of hydroponics where more than one moving part is involved.
It’s a popular form of hydroponics that is enjoyed by veteran gardeners and hobbyists.
What I like about the ebb and flow system is that it’s relatively easy and low-cost to build, as well as being highly customizable. Basic flood and drain systems can be built in minutes.
Also, you can add and remove plants at any given time without affecting the other plants in the system.
Ebb and flow systems can be highly versatile and grow a number of crops from large to small. Unlike NFT, you aren’t limited to plants with compact roots.
From microgreens to melons to tomatoes, you are really only limited based on the pot size you use and the size of your overall system.
Like other hydroponic methods, the ebb and flow system works on a simple idea: Plants are placed in a grow tray which is intermittently filled up with nutrient-rich water solution and then drained to a tank below.
The technique uses gravity just like NFT to send back the water to the reservoir to be reused later.
The reservoir contains a submersible pump linked to a timer. The timer is configured to turn on multiple times per day sending nutrient solution to the plants.
The frequency of flooding the plants depends on the size and kind of plants, temperature, humidity, and substrate.
This system may appear complicated to newcomers due to the components, but they all fit together very quickly and can be constructed in a short period of time.
Once installed, this system requires little maintenance and effectively produces plants while using very little electricity or water.
4. Drip System
Drip systems are another good option for home growers and commercial producers alike.
This is another hydroponic method that requires very few parts to construct and is therefore low cost and easy to maintain.
As you can see in the illustration above, a pump moves nutrient-rich water from the reservoir to be dripped onto the plant’s roots via the drip emitters to keep roots moist.
A big benefit here is you can easily control the watering schedule, drip locations, and nutrient amounts based on the needs of your plants.
Drip hydroponics is highly adaptable and practical to grow veggies, herbs, and fruit-bearing plants.
Again, in this setup, what you grow is really only limited by the size of your pots and the room around the setup.
For example, hops and large tomatoes are commonly grown in drip systems using buckets as reservoirs with trellises supporting the plant. This method allows large roots to be accommodated. Even roses can be grown in drip systems!
If you are only looking to grow small plants, like lettuce, I would suggest choosing another method, such as NFT or Deep Water Culture.
5. Deep Water Culture (DWC)
Deep water culture, also known as DWC, is a type of hydroponic system that uses a reservoir of nutrient-rich water to support plant growth.
DWC is my personal favorite due to its simplicity, low cost, and low maintenance.
DWC has two primary characteristics:
- Plants are grown in individual pots that are placed above the reservoir.
- Plant roots are constantly submerged in the water and given oxygen through an air pump and air stone.
This method lends itself to low-growing leafy greens and herbs, since tall plants can become top heavy and topple over!
If you do grow tall plants, just remember to stake them.
I also use my DWC setup for growing many types of perennials and vegetables, as well.
DWC is a very efficient way to grow plants because roots are constantly absorbing nutrients from the water. This allows plants to grow very quickly!.
As you can see in the picture, DWC does not need a water pump.
Instead, DWC often uses an air pump and air stone to put oxygen in the water.
The use of an air pump has a big benefit: Improving the aeration of roots enhances the absorption of nutrients and accelerates the growth rate of cells within plants.
Having said that, many plants will do quite well without the use of an air pump. Therefore, you can definitely build a DWC system without the need for electricity!
When choosing DWC for your garden, you may want to consider where you will place your garden. Water is quite heavy!
Building a large DWC system, and putting it on a surface that can’t hold the weight, like a flimsy bookshelf, could result in a nasty surprise!
6. Aeroponics
The final system we’ll discuss here is Aeroponics.
Aeroponics is an amazing type of hydroponics where plants are grown in an air or mist environment.
Note – It is considered a more advanced setup than something like DWC or NFT. Beginners are better off choosing another option.
In aeroponic systems, the plant roots are suspended in the air, and a nutrient solution is periodically sprayed onto the roots using misting nozzles.
This allows the roots to absorb the necessary nutrients and oxygen directly from the mist or fog.
Aeroponics offers amazing yields with very little water and nutrients.
Nearly any crop can be successfully grown in aeroponics! Just remember to build a support structure for taller plants.
A caution to those new to the hobby: Aeroponics can be tricky for first timers.
Unless you are going with an expensive, pre-fabricated system, a DYI aeroponics system can be frustrating to build and operate correctly as compared to the other options described above.
One important challenge I’ll call out is any disruption to the misting system can quickly lead to roots drying out and dying or at the least causing significant damage to the plant.
Having said that, for the brave and experienced, aeroponics can be very rewarding!
Hydroponic Methods Guide Wrap Up
As you can see, there are many hydroponic methods to consider.
Remember, there is no “best” system. Each one has its pros and cons.
The right approach for you will depend on your budget and goals.
Think about what you’ll be growing, your experience level, and how adventurous you’re feeling.
Honestly, the biggest challenge you may have is just having one type! I know that’s true for me!
Now that you’ve determined which system is right, you should spend some time learning about how to manage pH and maximize plant growth.
