Hydroponics is a catch-all term for various methods of growing plants without soil.
I say “catch-all” because there are many different types of hydroponic systems:
- Ebb and Flow: Repeated flooding and draining of roots
- Deep Water Culture (DWC): Constant suspension of roots in water
- Wick System: Grow tray sits on top of a water reservoir with a wick drawing the nutrient solution up into the grow tray
(Plus a few others.)
Aeroponics actually is just another type of hydroponic system.
Before we start comparing aeroponics vs hydroponics, let’s define what hydroponics is.
What Is Hydroponics?
Hydroponics is a method of growing plants without soil.
The word “hydroponics” was first coined in 1937 from the English word “hydro” (meaning water) and the Greek word “ponos” (meaning labor), which means “hydroponics” roughly translates to “working water.”
(Even “hydro” has its roots in ancient Greek. Doesn’t it seem like everything does?)
Growing without soil has one major advantage: The plant’s roots don’t need to expend valuable energy hunting for water, nutrients, or other resources. That means more energy goes toward leaf and stem growth and, ultimately, more yield.
What Is Aeroponics?
To reiterate the above, aeroponics is just another type of hydroponics.
(And, arguably, the most advanced type.)
In aeroponic systems, plants sit in a tray with their roots suspended in an enclosed environment below. Instead of being submerged in water–either temporarily (like Ebb and Flow) or permanently (like DWC)–the roots are misted with a fine, nutrient-rich spray.
3 Types of Aeroponic Systems
There are three types of aeroponic systems:
- Low-pressure aeroponics (“Soakaponics”)
- High-pressure aeroponics (true aeroponics)
- Ultrasonic foggers
While ultrasonic foggers can be used in aeroponic systems, you’re better off using either of the other two hydroponic systems. The problem with ultrasonic foggers is that the fog actually contains very little moisture with most of the water (and nutrients) falling to the bottom of the root chamber.
Low-Pressure vs High-Pressure Aeroponic Systems
With foggers excluded, let’s take a look at the high-level differences between low-pressure and high-pressure aeroponic systems.
| Low-Pressure | High-Pressure | |
|---|---|---|
| Cost | Low | High |
| Skill Required | Low | High |
| Droplet Size | Large | Fine |
| Specialized Equipment | Water pump | Accumulator tank Air compressor Fine spray mister heads Solenoid valve |
| Pros | Lower cost to get started and little specialized equipment necessary | Fine mist allows for better oxygen supply to roots and better nutrient uptake leading to higher yields |
| Cons | Low-pressure mist often has difficulty penetrating thick root masses | More challenging assembly and higher costs as pressurized accumulator tank replaces the water pump in low-pressure systems |
5 Advantages of Aeroponic Systems
This gives aeroponic systems five key advantages:
- No growing medium required
- Roots are constantly exposed to surplus oxygen
- More efficient use of nutrient solution
- Decreased risk of disease
- Higher yields
Let’s examine each in more detail.
1. No growing medium required
Because plant roots are suspended in air to be misted by nutrient-rich spray, there’s no need for a growing medium like Hydroton, coco noir, perlite, or vermiculite.
2. Roots are constantly exposed to surplus oxygen
While we all associate plants with needing carbon dioxide to thrive, their roots actually need a lot of oxygen.
Plant roots respire (or breathe) like animals do, using oxygen to generate the energy required to transport nutrients across the roots’ surface and into the plant.
Aeroponic systems, with roots constantly suspended in air and never fully submerged in water, are exposed to surplus amounts of oxygen, ensuring highly efficient nutrient uptake.
3. More efficient use of nutrient solution
Highly efficient nutrient uptake means less nutrient solution is needed.
While general hydroponic systems can reduce water usage by 90% compared to typical soil-based agriculture, aeroponic systems can reduce water usage by up to 98%.
This makes aeroponic systems up to five times more efficient than other types of hydroponic systems.
Not only is decreased water use better for you, but it’s also better for the environment. One of the major downsides of other hydroponic systems is the vast amount of wastewater they generate. That concern is mitigated with aeroponics.
4. Decreased risk of disease
In other hydroponic systems, plants share the same water reservoir and nutrient solution. If disease strikes one plant, it can quickly spread to others in your system.
Aeroponic systems isolate each plant as mist soaks plant roots separately with efficient uptake and little recycling. If disease strikes one plant, there’s a good chance it stays localized without infecting the rest of the system.
5. Higher yields
In aeroponic systems, roots are fed nutrient-rich solution in an oxygen-rich environment. That means plants don’t need to compete with each other for limited resources or expend energy growing roots to seek out nutrients.
Instead, all of that energy goes into faster growth and higher yields.
3 Disadvantages of Aeroponic Systems
Those five advantages all sound pretty great, so you should definitely get started on assembling an aeroponic system, right?
Well, maybe not.
There are three big disadvantages to aeroponic systems:
- Aeroponic systems are highly sensitive
- The initial cost can be high
- The learning curve can be steep
Like above, let’s look at these in more detail
1. Aeroponic systems are highly sensitive
A thriving aeroponic system is contingent upon all moving parts working together in concert. If the sprayers aren’t misting at the proper intervals or fail completely, the entire system can die off in just a few hours. Traditional hydroponic systems, with roots submerged in water or taking hold in a growing media, will survive much longer.
2. The initial cost can be high
True aeroponic systems (the high-pressure system from the table above) require a lot of specialized equipment to function.
In high-pressure aeroponic systems, mist needs to be sprayed for several seconds every few minutes. Let’s say the sprayers need to turn on and off every five minutes all day. That means 288 on/off cycles every 24 hours, which would wear out a water pump rapidly.
Instead, high-pressure systems use an air compressor attached to a pressurized accumulator tank to force fine mist out of the sprayer heads. A solenoid valve, controlled by a timer, opens/closes every few minutes. This setup is much more reliable but obviously much more costly to set up.
3. The learning curve can be steep
It’s also more difficult to grasp than a traditional hydroponics system. While anybody, beginners included, can begin their hydroponics journey with a robust aeroponic system, usually it’s better to begin with something more basic, like a hydroponic wick system, and then progress to a true aeroponic system.
Aeroponics vs Hydroponics: The Final Word
Like Ebb and Flow, DWC, wick systems, nutrient film technique, and others, aeroponics is just another type of hydroponic system and affords the following advantages compared to traditional hydroponics.
| Traditional Hydroponics | Aeroponics | |
|---|---|---|
| Advantages | Easier and less expensive to set up Easier to maintain | No growing medium required Roots exposed to surplus oxygen More efficient nutrient use Decreased risk of disease Higher yields |
Who should choose traditional hydroponics?
Because traditional hydroponic systems are easier to understand, less expensive to set up, and require less ongoing monitoring, they’re ideal for beginners just dipping their toes in the water (or, in this case, nutrient solution).
Who should choose aeroponics?
Optimized, efficient aeroponic systems give the best results, hands down. If that’s your primary concern, or if you really want to immerse yourself in the world of soilless agriculture (and are willing to weather the higher initial cost and frustrating fine-tuning) then aeroponics is for you.
If you have experience with maintaining aeroponic systems or think an important aeroponics vs hydroponics distinction has been left out, comment below.
